David Altmann

The prognosis of implantable defibrillator patients treated with cardiac resynchronization therapy: Comorbidity burden as predictor of mortality

Aims Comorbidity, such as myocardial infarction, diabetes, and renal failure, plays a pivotal role in the prognosis of a patient with arrhythmias. However, data on the prognostic impact of comorbiditiy in heart failure patients with cardiac resynchronization therapy and defibrillation (CRT-D) are scarce. The purpose of this study was to determine the impact of comorbidity on survival in CRT-D patients. Methods and results The study population consisted of 463 heart failure patients who received a CRT-D between 1999 and 2008 in Rotterdam and Basel. The Charlson comorbidity index (CCI) is often used as an adjusting variable in prognostic models. The Cox proportional hazards analysis was performed to determine the independent effect of comorbidity on survival. During a median follow-up of 30.5 months, 85 patients died. Mortality rates at 1 and 7 years were 6.3 and 32.3%. Cumulative incidence of implantable cardioverter defibrillator (ICD) therapy at 7 years was 50%, and death without ICD therapy was observed in 9% of patients. At least three comorbid conditions were observed in 81% of patients. Patients who died had a higher CCI score compared with those who survived (3.9 ± 1.5 vs. 2.9 ± 1.5; P < 0.001). An age-adjusted CCI score ≥5 was a predictor of mortality (hazard ratio 3.69, 95% CI 2.06–6.60; P < 0.001) independent from indication for ICD therapy, and from ICD interventions during the clinical course. Conclusion Comorbidity is often present in heart failure patients, and a high comorbidity burden was a significant predictor of mortality in CRT-D recipients. Comorbidity cannot predict appropriate ICD therapy. Death without prior ICD therapy occurs in a minor proportion of patients.

Validation of a novel spiral mapping catheter for real-time recordings from the pulmonary veins during cryoballoon ablation of atrial fibrillation

BACKGROUND The Achieve mapping catheter allows real-time recordings from the pulmonary veins (PVs) during cryoballoon (CB) ablation of atrial fibrillation (AF). OBJECTIVE To assess the clinical applicability of the Achieve mapping catheter and the value of real-time recordings from the PVs during CB. METHODS Patients with paroxysmal AF undergoing CB ablation were studied. Recordings from the PVs were analyzed during (real-time recordings) and after CB ablation and validated by using a variable circumferential mapping catheter (Achieve group; n = 20). A comparison was made by using a group of patients in whom CB ablation with a guidewire and a variable circumferential mapping catheter was performed (Guidewire group; n = 20). RESULTS Forty patients (age 58±11 years; ejection fraction 0.59±0.07; left atrial size 40±6 mm) with paroxysmal AF were included. In the Achieve group, real-time recordings from the PVs could be obtained in 40 of 80 (50%) PVs and could be seen more often at the left-sided PVs (25 of 39, 64%) than at the right-sided PVs (15 of 41, 37%; P = .02). Validation with a standard circumferential mapping catheter confirmed PV isolation in 75 of 80 (93%) PVs. After a single procedure and a follow-up of 14±4 months, 25 of 40 (63%) patients were in sinus rhythm with no significant difference between groups. CONCLUSIONS The Achieve catheter can be used as a substitute for a guidewire during CB ablation, but real-time recordings can be obtained only in half of the PVs and are not sufficient to accurately confirm isolation of all PVs.

Individually tailored vs. standardized substrate modification during radiofrequency catheter ablation for atrial fibrillation: a randomized study

Aims This randomized single-centre study sought to compare the efficacy and safety of pulmonary vein isolation (PVI) plus voltage-guided ablation vs. PVI with or without linear ablation depending on the type of atrial fibrillation (AF). Methods and results Overall, 124 ablation-naive patients with paroxysmal or persistent AF were randomized to PVI with (persistent AF) or without (paroxysmal AF) additional linear ablation (control group) vs. PVI plus ablation of low-voltage areas (LVAs) irrespective of AF type. Bipolar voltage mapping was performed during stable sinus rhythm. An LVA consisted of  ≥ 3 adjacent mapping points that each had a peak-to-peak amplitude ≤0.5 mV. After a mean follow-up of 12 ± 3 months, significantly more patients in the LVA ablation group were free from atrial arrhythmia recurrence >30 s off antiarrhythmic drugs (AADs) after a single procedure (primary endpoint) compared with control group patients [40/59 (68%) vs. 25/59 (42%), log-rank P = 0.003]. Arrhythmia-free survival on or off AADs was found in 33/59 control group patients (56%) and in 41/59 LVA ablation group patients (70%) (adjusted log-rank P = 0.10). During the 7 day Holter monitoring period at 12 months, significantly more patients in the LVA ablation group were free from arrhythmia recurrence on or off AADs [45/50 (90%) vs. 33/46 (72%), P = 0.04]. No between-group differences were observed regarding procedure duration, fluoroscopy time, and major complications. Conclusion In this single-centre study, individually tailored substrate modification guided by voltage mapping was associated with a significantly higher arrhythmia-free survival rate compared with a conventional approach applying linear ablation according to AF type.

Prevalence of severely impaired left ventricular ejection fraction after reperfused ST-elevation myocardial infarction.

BACKGROUND Preventive implantation of an implantable cardioverter defibrillator (ICD) early after myocardial infarction failed to demonstrate a survival benefit in patients with depressed left ventricular ejection fraction (LVEF). This may be explained by early recovery of the LVEF after percutaneous coronary intervention (PCI). We sought to determine the incidence of a sustained LVEF ≤35% in patients with severely depressed LVEF early after a revascularised acute ST-segment elevation myocardial infarction (STEMI). METHODS LVEF was assessed in patients with an acute STEMI treated with PCI in two Swiss high-volume centres within 10 days (in-hospital LVEF) after the STEMI. Those with an in-hospital LVEF ≤35% were scheduled for follow-up LVEF measurement within 6-8 weeks. RESULTS A total of 330 patients were included (79% male, mean age 63 ± 12 years). In-hospital LVEF measured 3 ± 3 days after STEMI was ≤35% in 32/330 patients (10%, 95% confidence interval (CI) 13%-67%). LVEF was available in 31/32 (97%) patients at follow-up 53 ± 19 days after STEMI and improved to >35% in 19 patients (61%, 95% CI 42%-78%). The incidence of a LVEF ≤35% at follow-up was 39% (12/31, 95% CI 22%-56%). CONCLUSION Our data demonstrate that the incidence of severely impaired LV function 53 ± 19 days after a STEMI treated with PCI is low. A severely depressed LVEF early after STEMI was present in 10% of all patients. Only 39% of these patients had a persistently impaired LVEF during follow-up. These findings support an expectant strategy before considering primary preventive ICD implantation after STEMI.