P1669Frequency and patterns of implantable cardiac defibrillator therapies in patients with ventricular assist devices

Purpose

Durable ventricular assist devices (VADs) use is a life-saving therapy in patients with end-stage heart failure. These patients are at high risk for ventricular arrhythmias. The pattern of ICD therapies in these patients is not well characterized.

Methods

Our single-center retrospective cohort included 86 patients with ICDs and VADs followed at our Centre. Data collected included frequency of ICD therapies, type of therapy (appropriate vs. inappropriate; shocks vs. anti-tachycardia pacing (ATP)), and time-course of therapies.

Results

36 patients (42%) received ICD therapy during a mean follow-up period of 13.6 months. There were 105 episodes (2.9 episodes/patient) during which ICD therapies were delivered, with a total of 379 individual arrhythmias treated (3.6 arrhythmias per episode of therapy). 61.4% of therapies were appropriate, 8.4% were inappropriate, and 31.6% were unknown. Of the 79 episodes treated with appropriate therapy, 36 episodes (46%) required ICD shocks, whereas 43 episodes (54%) were treated with ATP alone. Overall, 33% of the total cohort and 81% of patients who received therapy received at least one ICD shock. Twenty-two patients (61%) received therapy between 1–3 times, while the remainder (14 patients, 39%) received therapy 3–10 times. Eighteen (17%) episodes occurred within the first month after LVAD implantation, with 10 (10%) occurring between 1–3 months, 53 (50%) occurring between 3–12 months, and 24 (23%) occurring more than one year after VAD implantation.

Conclusion

Analysis of our VAD cohort revealed three important findings: 1. ICD therapy is very common (42%) in the first year especially after LVAD implantation; 2. Ventricular arrhythmias are highly clustered in this cohort; 3. ATP is frequently effective. These findings have important implications on device follow-up and programming for this expanding patient population.

Cryoablation for atrial fibrillation and antiarrhythmic drug pretreatment: a single referral center experience

OBJECTIVE

Pulmonary vein isolation (PVI) ablation has emerged as the gold standard of ablative strategies to treat medically refractory paroxysmal and persistent atrial fibrillation (AF). Regardless of the superiority of catheter ablation based on PVI over antiarrhythmic drug therapy, recurrence rates of AF remain higher than desired. PVI via cryoablation has rapidly become a mainstream treatment for AF, due to its effectiveness and fast learning curve. Our objective was to assess the safety and efficacy of cryoablation in a single referral center.

PATIENTS AND METHODS

This is a retrospective analysis of results after cryoablation treatment of AF over three years. 146 patients with AF underwent a cryoablation procedure in our clinical center and were followed-up for three years after the procedure. All patients received cryoablation of the pulmonary veins, although concomitant procedures were performed in 6 patients (re-ablation), including radiofrequency and cryoablation.

RESULTS

Cryoablation was clinically successful in 90.83% of the patients with paroxysmal AF and 60% of those with persistent AF. The clinical success of cryoablation was correlated with pretreatment with amiodarone and in the case of re-ablation. Concerning postoperative complications, major bleeding was correlated with female gender, treatment with rivaroxaban and amiodarone.

CONCLUSIONS

Among large trials, freedom from recurrent AF is about 65% with follow-up limited to 1 to 2 years. PVI via balloon cryoablation is a safe and efficient guideline-based treatment for AF, producing a durable event-free result in most patients out to 3 years with better outcomes than previously reported.

Cryoablation for atrial fibrillation and antiarrhythmic drug pretreatment: a single referral center experience

OBJECTIVE

Pulmonary vein isolation (PVI) ablation has emerged as the gold standard of ablative strategies to treat medically refractory paroxysmal and persistent atrial fibrillation (AF). Regardless of the superiority of catheter ablation based on PVI over antiarrhythmic drug therapy, recurrence rates of AF remain higher than desired. PVI via cryoablation has rapidly become a mainstream treatment for AF, due to its effectiveness and fast learning curve. Our objective was to assess the safety and efficacy of cryoablation in a single referral center.

PATIENTS AND METHODS

This is a retrospective analysis of results after cryoablation treatment of AF over three years. 146 patients with AF underwent a cryoablation procedure in our clinical center and were followed-up for three years after the procedure. All patients received cryoablation of the pulmonary veins, although concomitant procedures were performed in 6 patients (re-ablation), including radiofrequency and cryoablation.

RESULTS

Cryoablation was clinically successful in 90.83% of the patients with paroxysmal AF and 60% of those with persistent AF. The clinical success of cryoablation was correlated with pretreatment with amiodarone and in the case of re-ablation. Concerning postoperative complications, major bleeding was correlated with female gender, treatment with rivaroxaban and amiodarone.

CONCLUSIONS

Among large trials, freedom from recurrent AF is about 65% with follow-up limited to 1 to 2 years. PVI via balloon cryoablation is a safe and efficient guideline-based treatment for AF, producing a durable event-free result in most patients out to 3 years with better outcomes than previously reported.

Short-term effects of atrial versus atrio-ventricular pacing on myocardial ischaemia in coronary artery disease patients

This investigation was undertaken to evaluate the effects of short-term atrial vs atrio-ventricular pacing on myocardial ischaemia. The study was in two parts. In part one, 12 coronary artery disease patients were studied to investigate the effects of the two pacing modes on angina pectoris, coronary sinus O2 saturation and lactate. The two pacing modes were each applied for 5 min at 25 beats.min-1 more than the maximum heart rate of the exercise test. Coronary sinus O2 saturation and lactate were estimated before and after pacing. In part two, 13 patients with left anterior descending coronary artery disease were studied to investigate the effects of the two pacing modes on coronary flow reserve, using a Doppler catheter in the above mentioned branch after the administration of 10 mg intracoronary papaverine. The pacing rate was 15 beats.min-1 greater than the resting heart rate. Coronary sinus lactate and O2 saturation changes were the same and angina pectoris developed at about the same time from the beginning of pacing under both modes. Coronary flow reserve was 2.1 +/- 0.7 during atrial pacing and 2.1 +/- 1.1 during atrio-ventricular pacing (ns). It is concluded that short-term atrial and atrio-ventricular pacing have the same effects on myocardial ischaemia in coronary artery disease patients.

Total sympathetic activity and atrial natriuretic factor levels in VVI and DDD pacing with different atrioventricular delays during daily activity and exercise

The purpose of the study was to assess at rest and during exercise total sympathetic activity, as expressed by plasma cyclic AMP (cAMP) blood levels and sinus node activity (SNA), as well as atrial natriuretic factor (ANF) blood levels in VVI and DDD pacing with long and short atrioventricular delays in DDD paced patients suffering from complete heart block. Clinical parameters, such as exercise time, and arterial blood pressure (ABP) were also taken into consideration. Thirteen patients (six males, mean age 65 +/- 2 years), were examined randomly in VVI and DDD pacing with 100 and 150 ms atrioventricular delays (AVD). Plasma cAMP and ANF were measured at rest, at peak exercise and 15 and 30 min after the test. The cAMP at rest remained unchanged whatever the pacing mode or the AVD, but 30 min after exercise, the cAMP levels were statistically lower in DDD pacing with short AVD (100 ms) than in DDD with long AVD (150 ms) or VVI pacing (cAMP DDD/100 ms: 16 +/- 0.8 pmol.ml-1, cAMP DDD/150 ms: 20 +/- 2 pmol.ml-1, P < 0.01, cAMP VVI: 29 pmol.ml-1, P < 0.001). ANF plasma levels at rest were significantly higher in VVI pacing than in DDD modes, with either long or short AVD (ANF DDD/100 ms: 93 +/- 10 pg.ml-1, ANF DDD/150 ms: 100 +/- 13 pg.ml-1, ANF VVI: 150 +/- 16 pg.ml-1, P < 0.001, P < 0.03 respectively compared to VVI).(ABSTRACT TRUNCATED AT 250 WORDS)