The Fifth Decade of Cardiac Pacing
Book file PDF easily for everyone and every device.
You can download and read online The Fifth Decade of Cardiac Pacing file PDF Book only if you are registered here.
And also you can download or read online all Book PDF file that related with The Fifth Decade of Cardiac Pacing book.
Happy reading The Fifth Decade of Cardiac Pacing Bookeveryone.
Download file Free Book PDF The Fifth Decade of Cardiac Pacing at Complete PDF Library.
This Book have some digital formats such us :paperbook, ebook, kindle, epub, fb2 and another formats.
Here is The CompletePDF Book Library.
It's free to register here to get Book file PDF The Fifth Decade of Cardiac Pacing Pocket Guide.
Hypotensive side effects of ACE inhibitors and other vasodilators may be less pronounced, however, individual responses vary significantly. The dose of diuretics should be decreased if significant improvement in volume status is observed with CRT, to avoid prerenal azotemia and hypotension.
- Register for a free account;
- German Heavy Reconnaissance Vehicles!
- ATrial Tachycardia PAcing Therapy in Congenital Heart (AT-PATCH);
- Fastest Thoracic Insight Engine.
- Building and running modules.
Almost all patients undergoing CRT implantation are on antiplatelet or anticoagulation therapy, which increases bleeding risks. Compared to untreated patients, the likelihood of bleeding complications is doubled in patients on aspirin and quadrupled with dual antiplatelet therapy 1. Antiplatelet medications for primary prevention can be safely discontinued for a period of 5—7 days prior to the implantation. Dual antiplatelet therapy following PCI should not be discontinued in patients high risk for subacute stent thrombosis such as early after coronary stent implantation, with timing dependent on stent type Tompkins, Continuation of coumadin has a risk of postoperative pocket bleeding of 1.
After decades of debate, now there is evidence that perioperative antibiotic prophylaxis decreases risk of infectious complications.
The Fifth Decade of Cardiac Pacing | Ebook | Ellibs Ebookstore
Although some implant centers continue antibiotic utilization after the implantation, there is no proven benefit for this approach. Data regarding antibiotic prophylaxis for non-transvenous CRT implantation is scarce — generally, cardiothoracic surgical guidelines should apply as the optimal duration and selection of antibiotics may be affected by the given surgical approach Mertz, ; Edwards, and Engelman, Most interventional techniques may be safely utilized in the pacemaker laboratory.
It is preferable that the physician attempting a complex implantation or a device upgrade is well trained and current in the appropriate interventional and surgical techniques, or a physician with this training is immediately available.
- A Practical Guide to Cardiac Pacing, 6th Edition - PDF Free Download.
- I, Sniper (Center Point Platinum Mystery (Large Print)).
- Control Applications of Nonlinear Programming. Proceedings of the IFAC Workshop, Denver, Colorado, USA 21 June 1979;
- ATrial Tachycardia PAcing Therapy in Congenital Heart (AT-PATCH).
- Periodicity in Sequences Defined by Linear Recurrence Relations;
- Recipes for Gourmet Vegetables (Storeys Country Wisdom Bulletin A-106)?
- A View of the Ocean.
In case lead extraction is planned, a hybrid operating room or prompt access to surgical backup is mandatory. The incidence of unsuccessful implantations is declining, which is partly due to the advances in lead technology and implanting tools, however, interventional cardiology techniques have also been increasingly utilized with excellent efficacy and safety records. Minimally invasive surgical options are rapidly evolving and should be considered in case transvenous implantation is not feasible. Most common perioperative complications are failure to implant the LV lead, pocket hematoma, hemothorax or pneumothorax, CS dissection, cardiac perforation or tamponade, extracardiac stimulation, complete heart block, LV lead dislodgement, exacerbation of HF, acute renal failure, and death.
There is considerable variability in the ventricular activation pattern and distribution of mechanical dyssynchrony even in the LBBB population, and consequently inter-individual variability in the most optimal pacing site Auricchio, and Derval, Lead placement via endocardial and surgical epicardial approach may have more potential for individualized targeted pacing. Targeting methods include those assessing electrical, mechanical and anatomic parameters, but there is no consensus yet regarding the best method to improve long term outcomes Ansalone, ; Merchant, ; Gold, and Ypenburg, Imaging may help to select specific sites for left ventricular pacing based on anticipated optimization of electromechanical effects Toumoux, Echocardiography tissue Doppler or tissue synchronization imaging may identify LV sites with marked mechanical delay Cannesson, and Murphy, Pacing these sites may result in greater ventricular remodeling and improved clinical outcomes.
Currently there is not enough data supporting the role of acute hemodynamic measurements during implantation to target lead implantation Duckett, b. Multisite ventricular stimulation more than one LV lead may provide even greater benefits with more homogenous ventricular activation. More clinical data will be needed to evaluate whether it is superior to biventricular stimulation. Transvenous implantation should be the preferred way for CRT as most evidence is with this approach. The standard transvenous approach has significant drawbacks as it is dependent on the highly variable venous anatomy.
Even with successful lead placement, unstable position, high pacing threshold or phrenic nerve stimulation may hinder effective delivery of LV pacing. In case of an unsuccessful procedure, repeat transvenous procedure with a more experienced operator or with interventional backup is recommended, if the venous anatomy seems to be suitable for implantation.
In unsuitable cases, alternative approaches surgical epicardial, transseptal endocardial should be considered. Implantation should be performed from the left subclavian vein system, unless preexisting pathology venous occlusion, infection makes this approach unfeasible.
The right ventricular lead should be placed first as it is less likely to dislodge during manipulation of other leads and provides information about the position of the tricuspid valve and right atrial size. New guidelines emphasize the role of cardiac resynchronization therapy in subgroups of patients who already have conventional pacemakers, to avoid pacing-induced dyssynchrony and remodeling.
Upgrading an existing device may pose difficulties due to the necessity to operate in a previously scarred area and the presence of previously implanted leads in the venous system. The perioperative risks in these patients are significantly higher: the 6-month major complication rate was Subclavian venography with injection through the upper extremity veins is a simple and effective technique to evaluate venous anatomy prior to an upgrade or lead revision. Venoplasty may be performed if ipsilateral implantation is favored Worley, Extraction of non-used leads during an upgrade or revision has to be considered as the risk of long-term complications from abandoned leads is not negligible and correlates with the number of leads implanted and the number of prior procedures performed Diemberger, Implantation via the jugular or contralateral subclavian vein, with subcutaneous tunneling is required if the anatomy does not permit ipsilateral addition of a new lead.
Although primary transvenous device implantations are routinely performed using conscious sedation without much patient discomfort, deep sedation or general anesthesia may be required for lead tunneling Fox, In case lead extraction has to be performed prior to the upgrade, general anesthesia, invasive monitoring and availability of immediate surgical backup is recommended Kratz, For CS cannulation, a wide array of sheaths are available. The ostium may be probed with a standard angiographic soft-tip wire, an angiographic catheter such as Amplatz may be inserted into the sheath to adjust its distal curve.
Alternatively, a steerable CS EP catheter may also be used for mapping, individual practices vary significantly. Mapping with stiff catheters should be performed very cautiously as after overcoming any resistance from the Thebesian valve, the catheter may advance to the CS at an oblique angle, dissecting it, rendering continuation of the implantation procedure extremely difficult. This is most commonly encountered during insertion or advancement of the occlusion balloon catheter, as it has a relatively stiff distal portion.
Transesophageal echocardiography may facilitate CS cannulation when traditional methods have proven ineffective Bashir, In difficult cases intracardiac echocardiography may be more tolerable in patients under conscious sedation Shalaby, Cannulation of the CS is followed by coronary sinus angiography using an occluder balloon. Fluoroscopic acquisition should allow time to image late filling terminal branches, due to collateral flow. Some centers perform a single venography image, however, two orthogonal views RAO and LAO are preferred for better visualization of 3 dimensional anatomy.
A minority of centers perform rotational venography, which may provide more detailed information Blendea, The location and takeoff of the ostium may vary considerably, can be distorted by right atrial enlargement or prior surgery. Distally in the CS, the valve of Vieussens typically cm from the ostium may hinder cannulation of the distal vessel Ho, LV pacing leads may be implanted over a guidewire or directly.
The guidewire may help to achieve more distal position by providing a rail when advancing the lead in a tortuous vein. Care should be taken to place the preformed fixation mechanism curves, spiral or tags with adequate distal penetration, to have a large area of contact with the vein wall Hansky, Most current leads are at least bipolar with size and flexibility similar to previous unipolar leads. Figure 3. A quadripolar CS lead allows multiple pacing configurations, providing options to avoid phrenic nerve stimulation or sites with high threshold.
It also enables a more stable distal lead position, while still allowing pacing on the proximal electrodes if desired.
If the vein is tortuous, a stiffer wire or buddy wire may be used with caution, as the wall thickness and tear resistance of coronary veins is much less compared to coronary arteries. In case severe tortuosity or kinking of the vein does not allow adequate force transition to advance the lead, use of telescopic guides may be considered Russo, Inflated venogram occluder and coronary balloons can also be used as anchors to facilitate CS cannulation and left ventricular lead placement and help to recover lost CS and target vein access Worley, In case the target vein is stenotic, balloon angioplasty may be attempted.
The required instrumentation is the same as for coronary artery angioplasties. In the majority of cases with a focal stenosis or valve, balloon angioplasty is a safe method to facilitate passage of the lead. In selected cases coronary atherectomy or stent implantation may be required Soga, Angioplasty may also be used as a rescue when dissection of the coronary sinus or the target vein is observed during implantation, which would otherwise prohibit further attempts for lead placement Bosa, and Gutleben, In case of unfavorable coronary vein anatomy in the target area, dilatation and use of collateral veins may be considered Abben, Complications from venoplasty are rare, however, venous rupture has been reported Worley, Mostly short balloons with 3 mm diameter were used Luedorff, The presence of a persistent left superior vena cava may prohibit successful CRT implantation due to severely dilated CS and distorted anatomy, however, successful use of angioplasty in this case was reported Cagin, High pacing threshold or phrenic nerve stimulation may require repositioning of the lead from a stable to a less optimal position, where its fixation mechanism may not be as effective.
In these cases, a coronary stent implanted near the distal end of the lead may stabilize the new position. A large single center study of patients treated with stent implantation showed that the method was safe and effective in long term to prevent lead dislocation. The bare metal stents were implanted mm proximal to the most proximal electrode unipolar and bipolar LV leads. There was no evidence of mechanical damage to the lead or CS perforation.
During the follow-up of average Phrenic nerve stimulation was observed in 18 instances, and closed repositioning with an ablation catheter was performed in seven cases. In three cases the leads were extracted without complication after months infection, heart transplant Geller, Figure 4. Coronary sinus dissection is a rare complication of LV lead placement. It may be recognized as inability to pass instruments though a previously accessible area, and pooling of contrast after angiography. Although complete perforation is even less common and the pressure in the CS is low, cardiac tamponade may occasionally develop.
If the dissection is small, it may be possible to finish the implantation, although balloon angioplasty or stenting of the dissected segment may be necessary. In these cases, patients need to be monitored after the implantation, however, the exact duration that is required before a safe discharge is unknown Figure 5. Phrenic nerve stimulation was encountered in the distal lateral vein. In a more proximal position, the pacing threshold was acceptable with no diaphragmatic stimulation, however, the lead position was unstable. A bare metal coronary stent was implanted just proximal to the proximal electrode, after which the lead position stabilized.
Complicated CS anatomy may prohibit transvenous lead implantation even with extensive use of interventional techniques. The targeted lateral vein has a narrowed proximal segment with a kink, which did not allow lead advancement a. After passing a coronary guidewire, a bare metal stent was deposited into this region b. Although the guidewire easily passed through this area, lead advancement was still not feasible, the stent is clearly visible c.
Selective venography shows dissection proximal to the stent d. Even after multiple attempts with balloon angioplasty in this area, lead advancement was still not possible e. After multiple attempts with a selective guide and buddy wire, repeat venography shows dissection of CS with distal occlusion and staining, at this point the procedure was aborted f. No significant pericardial effusion or further sequelae were noted. Epicardial left ventricular stimulation poses a unique challenge as the electrode position has to be stable to provide effective cardiac resynchronization with low energy output, while avoiding phrenic nerve stimulation.
The coronary veins lack trabeculation and the thin wall prohibits the use of conventional screw-in active fixation leads. The majority of coronary sinus leads are passive fixation, which try to maintain stability with pre-shaped tips. Recently, built-in active lead fixation mechanisms became available. One third of the interventions are required more than 6 months after the implantation.
A dislodged coronary sinus lead can be the source of multiple complications, such as inadvertent stimulation of extracardiac structures, arrhythmia or perforation, and loss of effective cardiac resynchronization. Repositioning most of the time requires access to the lead via a device pocket revision. As open revision carries a higher risk of system infection, minimally invasive procedures should be considered when appropriate.
In some cases, the dislocation may be resolved by catheter-based techniques. In each case, an attempt has to be made to provide a more stable final lead position. A transfemoral approach was effective for the retraction of the LV lead from distal dislocation in a single center case series, where distal dislocation of the electrode lead to intolerable phrenic nerve stimulation Szilagyi, The CS was cannulated with an Amplatz catheter, then a coronary stent was introduced over a guidewire besides the lead into the side branch in 7 patients or in 2 patients, into the CS.
A steerable ablation catheter was looped around the LV lead in the atrium with bent tip and was drawn backwards together. The stent was then inflated to stabilize the lead tip in a new position.
During follow-up of median 7. There were no procedural complications or infections. Stabilizing the lead position with retained stylets is not recommended due to high risk of late lead failure Nagele, With active fixation of the CS leads, lead extraction may be an issue if the device has to be explanted. In the above mentioned case series, the few leads that had to be explanted and were previously stabilized with stent implantation, came out with manual traction most of the time, however, more data will be needed to assess if active anchoring of LV leads into the coronary veins poses any long-term risk.
Transseptal approach through the interatrial septum has been used for multiple interventional and electrophysiological procedures for decades. It is a relatively safe procedure in experienced hands, however, the facility should be prepared to address potential complications mainly pericardiocentesis and emergent periocardiotomy. Using the transseptal approach, a conventional endocardial PM lead may be implanted into the LV cavity for endocardial stimulation. The thromboembolic risks are not negligible and these patient require long term anticoagulation. Mitral valve damage and endocarditis are rare, but serious compliations.
The transseptal implantation begins with a standard transseptal puncture via the femoral vein van Gelder, After the successful puncture, full anticoagulation with iv. The puncture site is dilated with a mm balloon. A steerable EP catheter is advanced from the subclavian area towards the interatrial septum, then into the left ventricle after deflating the balloon. A sheath is then advanced into the LA over the EP catheter. The endocardial surface of the LV may be mapped with the EP catheter to localize a site most suitable for lead implantation, then a standard endocardial bipolar pacemaker lead is implanted.
Pacing and Sensing of Human Heart for over 31 Years with the Same Apparatus (Generator and Lead)
Using a modified technique, electroanatomical mapping may be used to precisely identify the area of latest activation in the LV Kutyifa, The main disadvantage of this technique is the unknown long term thromboembolic risk, which may be similar to a mechanical valve, with INR goals in the higher range Over an average of 85 month follow up of 6 patients in a case series, one patient had LV lead dislodgment at 3 months requiring reintervention. One patient had a transient ischemic attack, when anticoagulation was accidentally interrupted Pasquie, The need to start full dose anticoagulation immediately after the implantation increases the risk of periprocedural bleeding complications.
This technique is a feasible and safe second option with a benefit of endocardial pacing site and implantation procedure with no more burden to the patient than conventional transvenous CRT implantation. Main disadvantage is the need for long term anticoagulation. Patients who are ineligible for surgical epicardial implantation and have no contraindications for lifelong oral anticoagulation can be selected for this approach.
Biventricular pacing with endocardial stimulation may provide more homogenous intraventricular resynchronization than with epicardial stimulation, and is associated with better LV filling and systolic performance Garrigue, This approach was associated with considerable morbidity, requiring general anesthesia and longer recovery time. The prognostic relevance of clinical patient characteristics on survival was assessed univariately and multivariately by Cox's proportional hazards regression models. In these models all available baseline characteristics of our database see above were entered using no formal model building process.
The assumption of proportionality of the Cox models was verified by visual inspection of the log -log survival plots. For comparisons of more than two groups a closed test procedure was applied testing overall effects first followed by pairwise tests if the overall test was significant.
Therefore, no further adjustment was made for multiple testing. At the end of the study Mean age of deceased patients was Baseline patient characteristics are summarized in Table 1 : The median patient survival after pacemaker implantation was Baseline patient characteristics during the study: The first column summarizes the data over the year period, the following columns depict values during the three decades.
During the year period, both the indications for pacemaker implantation as well as the selection of the devices changed as new technologies developed: As depicted in Table 1 , the number of patients with sick-sinus syndrome treated with a pacemaker increased during the decades. Likewise, the use of pacemakers markedly changed during the study period: in the seventies, The age of the patients at implantation increased with the decades, as patients implanted were progressively older than those of the previous decades Table 1.
Similarly, the indications for pacemaker implantation shifted, with an increase in the number of patients implanted for sick sinus syndrome, and a decrease in the number of patients implanted for pauses in atrial fibrillation Table 1. Significant differences were seen in the survival of patients during the decades: As seen in Fig. Median survival was At 5 years after first pacemaker-implantation, Similarly, survival at years post implant was At 15 years after implantation, nearly a quarter This increase in survival times of patients was observed despite a significant increase in age at implantation, with a mean age at implantation of Kaplan—Meier analysis of survival of patients after pacemaker implantations.
The black line indicates survival of all patients, whereas the colored indicate survival of patients implanted during the three different decades. Long-term survival was significantly influenced by the type of arrhythmia leading to pacemaker implantation: Overall median survival was the longest in patients implanted for sick-sinus syndrome SSS with Similarly, survival proportions at 5, 10, 15 and 20 years were significantly different between groups Table 2.
AFIB denotes bradycardic atrial fibrillation. Estimated survival probabilities of pacemaker-patients a.
In addition, the proportion of women was significantly higher in the group of patients implanted for SSS During the study period, a total of women received pacemakers. Overall the mean age of women at pacemaker implantation was significantly higher than the age of men This difference increased throughout the three decades: In the first decade, mean ages of women vs men were Despite the higher age of women at pacemaker-implantation, their median survival time during the year study period was Similarly, survival proportions at 5, 10, 15 and 20 years differed significantly Table 2 , Fig.
Kaplan—Meier analysis of survival according to gender. As expected, age at implantation significantly influenced postoperative survival times: Patients aged less than 70 years at implantation had a median survival of Five-year survival was Finally at years survival proportions were Patients receiving a VVI-pacemaker had a significantly shorter median survival of Using subgroup analysis, baseline ECG-parameters were tested for an influence on survival: analysis was performed on the ECG at presentation, with measurement of the QRS-width of the predominant spontaneous rhythm.
However, when comparing all patients with either LBB or partial left bundle branch block left anterior or left posterior blocks to those with normal QRS-width revealed a significant difference in survival: median survival was No difference was seen between patients with right bundle-branch block and those with a normal QRS.
Regarding differences within the high degree AV-block groups, no differences were seen in survival between 2nd degree AV-block and 3rd degree AV-block. Also the age between the two groups of AV-block did not differ significantly. Included in the study population was a small proportion 0. The median follow up period after implantation for these was Kaplan—Meier survival is depicted in Fig. Multivariate analysis was performed to identify independent prognostic factors for survival after pacemaker-implantation.
Several factors were identified as independent predictors of survival in patients after pacemaker implantation:. The decade of implantation, with patients implanted during the last decade having a significantly longer survival compared to those implanted in the two earlier decades risk-ratio RR 0. As expected the age at implantation influenced survival inversely with younger patients having a significantly longer survival RR for each 1-year age increase 1.
Sick sinus syndrome was independently associated with better survival compared to patients with atrial fibrillation RR 0. Thus the index-arrhythmia remained an independent prognostic parameter after correction for differences in age and gender. Interestingly, symptoms leading to pacemaker implantation were independently associated with survival: Near-syncope was associated with a significantly longer survival than syncope or non-syncopal bradycardias RR 0.
The independent risk factors are summarized in Fig. Multivariate analysis: risk ratios of death of factors influencing survival after pacemaker implantation. A Multivariate analysis of the baseline patient characteristics —; B multivariate analysis of pacing mode. To assess whether the factors influencing survival of patients changed in the last decade from — , we performed a multivariate analysis in this subgroup of patients. Similar to the results in the whole population, age at implantation was an independent prognostic factors of survival RR: 1. Similar to the entire patient population, symptoms markedly influence survival, with near-syncope being an independent factor for improved survival compared to syncope or non-syncopal bradycardias RR 0.
Since the implantation of the first artificial pacemaker in these devices have become the treatment of choice in bradycardias. Despite its widespread use, overall long-term survival of pacemaker patients has been addressed by only few studies during the last three decades. To avoid a bias due to the learning curve of the very first pacemakers, the study period was started in , whereas the first pacemaker in our hospital was implanted in Thus before the beginning of the study, we had already gathered experience in more than pacemaker-patients treated by the same team ofphysicians.
One of the main results of this study is the longevity of pacemaker patients: approximately one-third of the patients survived for 15 years, with one-fifth of patients surviving up to 20 years. Given the fact, that due to medical advances the life expectancy continues to rise as seen during the last decade this has clear implications on device selection for the subgroup of very long-term survivors: To avoid the risk and the cost of repeated exchanges of pacemaker-devices due to battery depletion, the implantation of devices with a longer battery life and the use of electrodes with high impedance to preserve energy needs to be considered in these groups.
We found several highly significant factors, which influence survival: First of all, gender is an independent prognostic factor for survival in our study: It is well known that the life expectancy of women is higher, and that cardiovascular diseases are delayed in the female gender.
Despite women being more than 2 years older at the time of implantation, their overall median survival is still more than 2 years longer compared to men, and the gender difference in survival even increased during the last decade. Even though gender differences in survival have been reported, neither a differential influence depending on the type of arrhythmia nor this magnitude have been previously reported. Secondly, the symptoms leading to pacemaker implantation are independently associated with survival: Patients experiencing classical Adam—Stokes type syncope and those with asymptomatic bradycardia i.
ECG-documented bradycardia have identical, but worse survival compared to patients with near-syncope as the initial symptom. Clearly it would be interesting to compare the survival of these patients with and without pacemaker therapy, to analyse if pacemaker implantation affects survival at all in this subgroup, however, to the best of our knowledge, no study has yet addressed this question.
Thirdly, the choice of VVI pacing influenced survival adversely, a difference which was more evident during the first two analysed decades. Interestingly, there was no significant difference between AAI and dual-chamber pacemakers, which were both associated with a markedly longer survival than VVI. In a retrospective study of short-term survival with a follow-up of 2 years, Lamas et al.
Previous studies showed no significant differences in survival but in symptoms or secondary end-points, especially in patients with sick-sinus syndrome. The other influencing factors remained significant. One of the main limitations of this study is that we could not control for other factors influencing survival such as left ventricular ejection fraction, medication or other concomitant diseases , as data collection was started in the seventies.
However, no randomized trial has been conducted to date with a similar number and duration of follow-up in pacemaker patients. This clearly shows, that a large, randomized study on the very long-term effects beyond the usual 4—6 years of follow up in previously published trials of pacing mode on survival are warranted. Another limitation of this study is the number of patients with loss of follow-up: We have used a conservative approach and classified patients who were lost for follow-up as being alive on the day of their last visit and being lost for follow-up thereafter.
Given the mean age of these patients 76 years it is likely, however, that a substantial proportion of these patients died thereafter, but our telephone follow up which was performed the day after their missed appointment, i. As these patients were censored at their last visit, this should not affect the estimated survival probabilities according to the Kaplan—Meier method. In the subset of older patients, Jahangir et al. Due to the size and the heterogeneity of this subgroup, a multivariate analysis was not attempted. However, this subgroup exhibits both a high mortality rate 10 of 34 children died during follow-up but also potentially a very long duration of pacemaker therapy.
Clearly, a larger study on the characteristics of long-term survivors after pacemaker implantation in children would be very interesting.