[Impact of telemetric management on overall treatment costs and mortality rate among patients with chronic heart failure]. / Einfluss einer telemedizinisch unterstützten Betreuung auf Gesamtbehandlungskosten und Mortalität bei chronischer Herzinsuffizienz.

BACKGROUND AND OBJECTIVE: The rising prevalence of chronic heart failure (CHF) has led to an increase in total treatment expenditures. A medical care programme of telemetry was developed to reduce the number of patients with decompensated CHF, hospital admissions and overall treatment cost. PATIENTS AND METHODS: As part of a prospective controlled study the body weight of 251 patients with CHF was monitored over one year. The supervising center contacted the patients whenever their body weight exceeded a threshold value. Patients were phoned by a designated personal adviser and received regular informative material and advice by specialist medical personnel. Patients' general practitioners had been involved in recruiting patients and by regularly sending them follow-up reports. Another group of 251 patients who had not received the described telemetric intervention served as control. RESULTS: The mean age of the patients was 71.7 years, lower than the 76.4 years of the control group. More patients in the intervention groups were in NYHA class III and IV than in the control group (52 % vs 36 %). After an average observation period of 12 months the duration of hospital stay had been reduced by 48 % (p = 0.01), the hospital costs by EUR 7128 per patient p = 0.01), while drug expenditure had increased by EUR 245 per patient (not significant). The total costs had thus fallen by EUR 6993 per patient (-39.5 %; p = 0.05). The mortality rate of 14.7 % in the intervention group was significantly lower than that of the control group of 27.1 % (p = 0.001). The reduction in costs and mortality rate was clearly greater for men than women. Total expenditure had been highest for patients who had died. CONCLUSION: The results indicate that total treatment costs and mortality rate can be reduced by telemetric monitoring of patients in CHF, especially in men.

[Cardioverter-defibrillator implantation in the heart catheterization laboratory--observations with 105 patients]. / Kardioverter-Defibrillator-Implantation im Herzkatheterlabor--Beobachtungen bei 105 Patienten.

Today, we are facing an exponential increase in implantation of cardioverter defibrillators (ICD). The intraoperative and follow-up results are reported in 105 patients (pts) with ventricular tachyarrythmias who underwent ICD implantation in the catheterization laboratory. Fifty-seven pts (54%) hat their first ICD implant (G 1), whereas 46 pts (44%) underwent pulse generator replacement or electrode revision (2 pts, 2%) (G 2). In all pts, ICD implant or pulse generator replacement was performed under general anesthesia from the beginning. In 57/58 pts (98%) in G 1, ICD implantation was possible with a mean defibrillation threshold (DFT) of 13 +/- 8 joules. One patient hat a DFT of > 25 joules and ICD implantation was not achieved. This patient underwent epicardial lead implantation 1 day later. One patient in G 1 had a vessel rupture (v. subclavia) intraoperatively. During a mean follow-up of 5 +/- 2 (< 1-13) months, three pts (3%) died from congestive heart failure, 2, 4 and 6 months after device implantation. An infection occurred in 1 patient in G 2, 3 months after generator replacement. Our data show that in the majority of patients ICD implantation in the cath-lab is possible, safe, and the complication rate is low. Therefore, ICD implantation in the cath-lab can generally be recommended.

Implantation and follow-up of a third-generation cardioverter defibrillator: comparison of epicardial and nonthoracotomy defibrillation lead system.

OBJECTIVE: The intraoperative and follow-up results were compared in 67 patients with ventricular tachyarrhythmias who underwent implantation of the Ventritex Cadence defibrillator with either epicardial patch (EPI, 25 patients) or nonthoracotomy CPI Endotak (ENDO, 42 patients) defibrillation lead systems. RESULTS: There was no significant difference between groups in age, sex, structural heart disease, ejection fraction, arrhythmia history, or drug therapy. Successful implantation was accomplished in all patients using either lead system. In the ENDO group, 35 patients (83%) had a defibrillation threshold < or = 550 V and did not require a subcutaneous patch. Intraoperatively, the defibrillation threshold was 453 +/- 139 V (13 +/- 9 J) for EPI and 490 +/- 113 V (15 +/- 8 J) for ENDO (P = NS). There were no perioperative deaths in either group. At predischarge testing, the defibrillation threshold was 445 +/- 183 V (14 +/- 12 J) for EPI and 439 +/- 133 V (13 +/- 7 J) for ENDO (P = NS). During a mean follow-up of 16 +/- 8 months, there were no sudden deaths, and four patients died from congestive heart failure (3 EPI, 1 ENDO). During follow-up, 916 spontaneous arrhythmia episodes occurred in 16 of 25 EPI patients (64%) and 967 episodes occurred in 31 of 42 ENDO patients (74%) (P = NS). The number of episodes detected as ventricular fibrillation were 192 for EPI (21%) and 232 for ENDO (24%), with first shock success in 76% and 75%, respectively; all episodes were successfully terminated by the device. In the remaining episodes detected as ventricular tachycardia, antitachycardia pacing was attempted and was successful in 672 of 724 episodes (93%) with EPI and 666 of 735 episodes (91%) with ENDO lead systems (P = NS). Acceleration of ventricular tachycardia with antitachycardia pacing occurred in 21 episodes (3%) with EPI and in 37 episodes (5%) with ENDO leads (P = NS). CONCLUSIONS: A nonthoracotomy approach using the third generation cardioverter defibrillator Cadence V-100 is safe and effective and has clinical results that are not significantly different from epicardial defibrillation lead systems.

[Experiences with the new cardioverter-defibrillator Ventak PRxII]. / Erfahrungen mit dem neuen Kardioverter-Defibrillator Ventak PRxII.

Clinical safety and efficacy of the new third-generation implantable cardioverter defibrillator (ICD) Ventak PRxII was studied in 50 patients (pts) with ventricular tachycardia (VT) and/or fibrillation (VF). In 23 pts (46%) the ICD was implanted with a transvenous lead system as first implant and 27 pts (54%) received the Ventak PRxII as generator replacement. Intraoperatively, the mean defibrillation threshold (DFT) was 13 +/- 8 joules and 12 +/- 8 joules, respectively. One pt died perioperatively. During a follow-up of 5.3 +/- 3.8 months 3 patients died due to heart failure. During follow-up 1060 arrhythmia episodes (AE) occurred and were terminated primarily by countershock in 121 AE (11%). Antitachycardia pacing (ATP) was tried in 939 AE (89%) and was successful in 878 AE (94%). Acceleration was present in 6 AE (< 1%). We conclude that there is a high efficacy rate in AE termination by the Ventak PRxII, using ATP or countershock. Therefore, the Ventak PRxII allows a flexible approach to cardiac rhythm management.

[10 years of therapy with implantable defibrillators--observation in 353 patients]. / 10 Jahre Therapie mit implantierbaren Defibrillatoren--eine Beobachtung bei 353 Patienten.

Since January 1984, the cardioverter-defibrillator (ICD) has been implanted in 353 patients (pts). Epicardial ICD implantation was performed in 207 pts and 146 pts underwent non-thoracotomy ICD implant. Overall operative mortality was 3% (12/353 pts) and was significantly higher in pts with epicardial ICD implantation (11/207 pts, 5%) than in patients who received non-thoracotomy ICDs (1/146 pts, < 1%) (p < 0.05). During a mean follow-up of 25 +/- 23 months, 63 pts (19%) died: 8 pts (0.8% per year) from sudden arrhythmic death and 6 pts (0.8% per year) suddenly without an underlying arrhythmia. Cardiac death was observed in 36 pts (4% per year) and 13 pts (2% per year) died from other causes. Appropriate ICD discharges were observed in 245 pts (72%) with a mean incidence of 22 +/- 44 IC discharges per pt. In pts with third-generation ICDs, 3,542 ventricular tachyarrhythmias (VTA) were observed and terminated by primary ICD shocks in 778 VTA (22%). Antitachycardia pacing was attempted in 2,764 VTA (78%) and was successful in 2,484 VTA (90%).

Cardioverter-defibrillator implantation in the catheterization laboratory: initial experiences in 48 patients.

The exponential increase in cardioverter-defibrillator implantations has resulted in a need for safe implantations that do not require long waiting periods. We report intraoperative and follow-up results in 48 patients with ventricular tachyarrhythmias who underwent cardioverter-defibrillator implantation in the catheterization laboratory. Twenty-six (54%) patients had their first cardioverter-defibrillator implant (group 1), and 22 (46%) patients underwent pulse-generator replacement (group 2). In all patients, cardioverter-defibrillator implant or pulse-generator replacement was performed with the patient under general anesthesia. In 25 (96%) of 26 patients in group 1, cardioverter-defibrillator implantation was possible with a mean defibrillation threshold of 13 +/- 8 J. One patient had a defibrillation threshold of > 25 J, and therefore cardioverter-defibrillator implant was not achieved. This patient underwent epicardial device implantation 1 day later. Another patient in group 1 had vessel rupture (vena subclavia) intraoperatively. During a mean follow-up of 2 +/- 1 months, two patients died from congestive heart failure 2 and 4 months after device implantation. An infection occurred in one patient in group 2, 3 months after generator replacement. In conclusion, these data show that in the majority of patients cardioverter-defibrillator implantation in the catheterization laboratory is safe and has a low complication rate and therefore can generally be recommended.

[The role of anti-tachycardia stimulation in patients with 3rd-generation defibrillators]. / Die Bedeutung der antitachykarden Stimulation bei Patienten mit Defibrillatoren der 3. Generation.

The most effective antitachycardia pacing mode (ATP) is still a matter of debate. Randomized prospective testing of 5 different ATP modes was performed in 82 patients (pts) prior to and after cardioverter defibrillator (ICD) implantation. The 5 ATP modes included 3-4 stimulation attempts with 4-10 adaptive scanning burst pulses. Adaptive burst coupling interval was 75% in mode A, 81% in mode B, 69% in mode C, 72% in mode D, and 88% in mode E. Auto-decremental scanning within bursts was 8 ms in modi A, B, and C, and 10 ms in modus E; autodecremental scanning between bursts was 8 ms in modi B and C, and 10 ms in modus D. During the pre-op electrophysiologic study (EP), termination (TR) of induced ventricular tachycardia (VT) was possible in 69% and by pre-discharge EP in 53%. Acceleration (AC) rates were 16% pre-op and 32% post-op (p = ns). There were no significant differences in TR or AC between modes A-E. During a mean follow-up of 18 +/- 4 (< 1-41) months, 3182 arrhythmia episodes (AE) occurred: 344 AE (11%) were terminated by primary ICD shocks and ATP was attempted in 2838 AE (89%) and was successful in 2576 AE (91%). AC occurred in 87 AE (3%) and ATP was without effect in 175 AE (6%). Our data show that ATP is helpful in patients with third-generation ICDs and is very effective during follow-up. However, there is no ideal ATP-mode visible in the present study.

Epicardial and nonthoracotomy defibrillation lead systems combined with a cardioverter defibrillator.

The intraoperative and long-term results were reviewed in 67 patients who underwent implantation of the Ventritex Cadence defibrillator with either epicardial patch (EPI, 25 patients) or nonthoracotomy CPI Endotak (ENDO, 42 patients) defibrillation lead systems. In the ENDO group, 35 patients (83%) had a defibrillation threshold (DFT) of < or = 20 joules and did not require a subcutaneous patch. Intraoperatively, the DFT was 13 +/- 9 joules (mean +/- SD) for EPI and 15 +/- 8 joules for ENDO (P = NS). There was no perioperative death in either group. During a mean follow-up of 12 +/- 8 months, there was no sudden death, and four patients died from congestive heart failure (3 EPI, 1 ENDO). During follow-up, 875 spontaneous arrhythmia episodes (AE) occurred in 15 of 25 EPI patients (60%), versus 652 in 28 of 42 ENDO patients (67%; P = NS). Ventricular tachycardia at a rate > or = 222 beats/min or ventricular fibrillation represented 167 AE for EPI (19%) and 182 AE for ENDO (28%), and was terminated by the first shock in 76% and 75% of attempts, respectively. Ventricular tachycardia at a rate < 222 beats/min represented a total of 1,178 AE and antitachycardia pacing was successful in 660 of 708 AE (93%) with EPI and 414 of 470 AE (88%) with ENDO lead systems (P = NS). Therefore, a nonthoracotomy approach using the Cadence V-100 is safe and effective and has clinical results that are not significantly different from epicardial defibrillation lead systems.

Nonpharmacological therapy of ventricular tachyarrhythmias: observations in 554 patients.

It has been shown that conventional antiarrhythmic drug treatment is debatable, and there is growing interest in nonpharmacological techniques. We studied the outcome of 554 patients with ventricular tachycardia (VT) or ventricular fibrillation (VF) who underwent nonpharmacological techniques from March 1980 to June 1994 at our institution. Catheter ablation was performed in 51 patients (G1), map guided surgery in 147 (G2), and cardioverter defibrillator implantation (ICD) in 356 (G3). During a mean follow-up of 37 +/- 12 (< 1-137) months, incidence of sudden death (G1 4%, G2 6%, G3 3%) and cardiac death (G1 7%, G2 16%, G3 8%) were relatively low, and there was no significant differences between G1-G3. VT/VF recurrences occurred more frequently in G1 (57%) than in G2 (18%) (P < 0.01). ICD discharges occurred in 69% of patients. We conclude that nonpharmacological techniques lead to low sudden death rates; however, there is a high rate of recurrence in G1. Risk stratification is necessary to select the ideal therapy for each individual patient.

Role of antitachycardia pacing in patients with third generation cardioverter defibrillators.

The most effective antitachycardia pacing (ATP) mode is still a matter of debate. Randomized prospective testing of 3 different ATP modes was performed in 65 patients (pts) prior to and after cardioverter defibrillator implantation (Ventak PRx 36 pts, Cadence V 100 29 pts). All 3 ATP modes included 4 stimulation attempts with 4-7 adaptive scanning burst pulses. Adaptive burst coupling interval was 75% in mode A, 81% in mode B and 69% in mode C. Autodecremental scanning within bursts was 8 msec in all, decremental scanning between bursts was 8 msec in modes B and C. Each ATP mode had to be tested 3 times; all 3 ATP modes were randomly applied to each pt. During preoperative testing 91 of 133 VT episodes (68%) could be terminated by ATP. Termination was achieved in 68% with mode A, 68% with mode B and 73% with mode C. During predischarge testing, 251 VTs were induced and ATP was successful in 147 VTs (59%). Termination rate was 56% with mode A, 68% with mode B and 50% with mode C. During the mean follow-up of 12 months, 2301 arrhythmia episodes (AE) occurred. ATP was performed in 2097 AE (91%) and successful in 1920 AE (92%). Acceleration of VT occurred in 65 AE (3%) and unsuccessful ATP was observed in 112 AE (5%). It is concluded that ATP in general is highly effective in pts with sustained VT. None of the tested ATP modes, however, proved to be superior to the other.

Risk and benefit of additional aortocoronary bypass grafting in patients undergoing cardioverter-defibrillator implantation.

It is unclear whether additional aortocoronary bypass grafting should be performed in patients who need an automatic implantable cardioverter defibrillator (ICD) in one- or two-step procedures. Therefore we studied the follow-up of 139 patients who underwent epicardial implantation of the cardioverter defibrillator (CD). All patients had coronary artery disease and recurrent ventricular tachycardia or fibrillation. Eighty-nine patients had implantation of the CD without additional surgical approaches (group G1), and 50 patients had concomitant aortocoronary bypass grafting (group G2). Perioperative mortality (within 30 days after CD implant) was 1 (1%) of 89 patients in G1 and 6 (12%) of 50 patients in G2 (p < 0.01). During the mean follow-up of 26 +/- 20 months, sudden death occurred in four (4%) of 89 patients in G1 and two (4%) of 50 patients in G2. Twenty-three (17%) patients died of cardiac failure (18 [20%] patients in G1 and 5 [10%] patients in G2). ICD discharges occurred in 69 (78%) of 89 patients in G1 and in 36 (72%) of 50 patients in G2. The mean incidence of ICD discharges was 23 +/- 69 shocks per patient in G1 and 18 +/- 25 shocks per patient in G2 (p = NS). We conclude that concomitant aortocoronary bypass grafting during CD implantation leads to a higher perioperative mortality. Avoidance of myocardial ischemia does not significantly influence sudden death mortality nor markedly reduce the number of ICD discharges.

Role of interventional therapy in patients with coronary heart disease and life-threatening ventricular tachyarrhythmias.

This study includes 357 patients with coronary heart disease and life-threatening ventricular tachyarrhythmias. Thirty-three patients (10%) underwent direct current (DC) catheter ablation (group 1), 121 (34%) mapping-guided surgery (group 2) and 203 (56%) received an implantable cardioverter defibrillator (ICD) (group 3). The mean follow-up was 35 +/- 25 months in group 1, 41 +/- 37 months in group 2 and 22 +/- 22 months in group 3. During follow-up, 6 patients (18%) died in group 1, 45 (37%) in group 2 and 46 (23%) in group 3. Sudden death occurred in two patients (6%) in group 1, 10 patients (8%) in group 2 and eight patients (4%) in group 3. Non-fatal recurrences group were observed in 19 patients (57%) in group 1 and in 16 patients (14%) in group 2. ICD discharges occurred in 175/203 patients (86%) in group 3 with a mean number of 18 +/- 28 ICD shocks per patient. Our data show that catheter ablation has a low incidence of sudden death but a high incidence of non-fatal recurrences. Mapping-guided surgery yields low rates of sudden death or recurrence. Patients with an ICD have a low sudden death rate. A treatment algorithm is necessary to evaluate patients at high risk for sudden death and to choose the right patient for the right treatment.

[The importance of the underlying disease for outcome of patients with implanted automatic defibrillators]. / Die Bedeutung der Grunderkrankung für den Krankheitsverlauf bei Patienten mit implantiertem automatischen Defibrillator.

It is unclear whether the outcome of patients with implanted cardioverter defibrillator (ICD) is influenced by the underlying etiology or not. Therefore, we studied the follow-up of 271 patients who underwent ICD implantation for life-threatening ventricular tachyarrhythmias. Coronary artery disease was present in 203 patients (75%) (G1), dilated cardiomyopathy in 36 patients (18%) (G2), while 32 patients (12%) (G3) had an "arrhythmogenic" ventricle (dysplasia, valvular disease, idiopathic arrhythmias). Mean left ventricular ejection fraction was 30 +/- 11% in G1, 33 +/- 13% in G2 and 48 +/- 13% in G3. Perioperatively, 12/271 patients (4%) died. During the mean follow-up of 21 +/- 17 (< 1 to 99) months, 52/259 patients (20%) died: 31% (11/36 patients) in G2, 19% (36/193 patients) in G1 and 17% (5/39 patients) in G3. There was a low incidence of sudden death (SD) (4%, 2% per year) without significant differences between G1 (3%), G2 (8%) and G3 (3%). In addition, no significant differences were observed in cardiac mortality (CD) between G1 (10%), G2 (14%) and G3 (3%) (p = n.s.). ICD discharges occurred in 188 patients (69%); ICD discharges occurred in G1 in 138 patients (68%), in G2 in 27 patients (75%) and in G3 in 23 patients (72%). The mean incidence of ICD discharges per patient was 16 +/- 10 shocks in G1, 24 +/- 8 shocks in G2 and 18 +/- 8 shocks in G3. After ICD implant, complications occurred in 67 patients (23%). Our data show that the ICD is highly effective in preventing sudden death independent on the underlying etiology.(ABSTRACT TRUNCATED AT 250 WORDS)

Initial experience with a new transvenous defibrillation system.

The clinical efficacy and safety of a new bidirectional transvenous defibrillation endocardial lead system (ELS) was studied in 39 patients with ventricular tachycardia (VT) or fibrillation (VF). There were 28 patients with coronary disease and 11 patients with nonischemic VT/VF. Fourteen patients received the ELS combined with antitachycardia pacing devices (Ventak PRx 1700, CPI) and 25 patients with the Ventak P or P2 (CPI). Implantation of the ELS was attempted in 47 patients. Intraoperatively, the mean defibrillation threshold (DFT) was > 25 joules in five patients and no reliable ELS position was found in three other patients. These eight patients underwent thoracotomy and epicardial leads implantation. The mean DFT was < or = 20 joules in all 39 patients and the mean DFT was 18 joules. During the mean follow-up of 8 +/- 2 months two patients (5%) died suddenly. Complications occurred in two patients (5%).

Clinical efficacy and safety of the new cardioverter defibrillator systems.

Clinical efficacy and safety of two new third-generation implantable cardioverter defibrillators (ICD) were studied in 38 patients with ventricular tachycardia (VT) or fibrillation (VF). There were 31 patients with coronary disease, three patients with right ventricular dysplasia, one patient with dilated cardiomyopathy, and three patients with valvular disease. Twenty-four patients (group I) received an ICD with monophasic (Ventak PRx 1700, CPI) and 14 patients (group II) with biphasic shocks (Cadence V 100, Ventritex). Intraoperatively, the mean defibrillation threshold was significantly lower in group II than in group I, both in patients with induced VT (group I 11.0 +/- 6.3 joules; group II 5.8 +/- 1.3 joules) (P < 0.01) and induced VF (group I 17.5 +/- 4.6 joules; group II 9.6 +/- 5.2 joules) (P < 0.01). During the mean follow-up of 12 +/- 7 months four patients (11%) died. 865 arrhythmia events (AE) occurred and were terminated by ATP (671 VTs, 78%). Acceleration of VTs was observed in 28 AE (3%) and ATP was unable to interrupt 58 AE (7%). ICD shocks were delivered as a first therapy in 108 AE (13%).

[Results and experiences of transvenous endocardial defibrillator therapy]. / Ergebnisse und Erfahrungen der transvenösen endokardialen Defibrillatortherapie.

We studied the follow-up of 72 patients who underwent implantation of a transvenous defibrillation lead system (ELS) (Endotak, CPI). All patients had ventricular tachycardia (VT) or fibrillation (VF) refractory to antiarrhythmic drug therapy. There were 51 patients with coronary disease and 21 patients had non-ischemic VT/VF. ELS was combined with a subcutaneous patch in 52 patients and implanted alone ("single lead only") in 20 patients. 40 patients received the ELS combined with antitachycardia pacing devices (Ventak PRx, CPI; Cadence, Ventritex) and 32 patients with the Ventak P 1600 or P2, CPI. Implantation of the ELS was attempted in 80 patients and performed in 72 patients (90%): Intraoperatively, the mean defibrillation threshold (DTF) was > 25 Joule (J) in five patients and no reliable ELS position was possible to achieve in three patients. These eight patients underwent thoracotomy with epicardial patch implantation. The mean DFT was < or = 20 J in all 72 patients with a mean DFT of 14 +/- 8 J in VT patients and 17 +/- 10 J in VF patients. Two of 80 patients (3%) died: one patient died intraoperatively and one during the mean follow-up of 6 +/- 2 (< 1 to 18) months. Complications occurred in three patients (4%): Dislocation of the Endotak electrode was observed in two patients (3%) and one patient developed pneumothorax postoperatively. Our data show that the ELS is most suitable in the majority of patients with VT/VF and is the approach of first choice for cardioverter defibrillator implantation at the present time. However, despite a relatively low intra- and perioperative complication rate, this approach should not be performed in institutions without cardiac surgery.