Akli Otmani

Atrial Septal Versus Atrial Appendage Pacing: Feasibility and Effects on Atrial Conduction, Interatrial Synchronization, and Atrioventricular Sequence

HERMIDA, J.‐S., et al.: Atrial Septal Versus Atrial Appendage Pacing: Feasibility and Effects on Atrial Conduction, Interatrial Synchronization, and Atrioventricular Sequence. Atrial septal (Se‐P) and atrial appendage pacing (Ap‐P) were compared in a randomized, controlled study to assess the feasibility, the reliability, and the effects of Se‐P on atrial conduction, interatrial synchronization, and the AV sequence. The main baseline characteristics of the patients were comparable in both groups. There was no difference in feasibility or reliability between the two techniques. Compared to Ap‐P (n = 28) , Se‐P (n = 28) decreased the P wave duration, left atrial electromechanical delay (LAEMD), and interatrial interval (−1.6% vs +28%, P < 0.001; −3% vs + 30%, P < 0.001; −130% vs + 78%, P < 0.001 ); it induced a smaller increase of the right AEMD, a slight reversal of the timing of the atrial systoles and a shortening of the PR interval (−13% vs + 25%, P < 0.001 ) and of the interval separating atrial systoles from ventricular activation. Finally, the shortening of the PR interval was smaller during high Se‐P versus low Se‐P. Se‐P avoids the undesirable prolongation of the atrial, interatrial, and AV conductions observed during Ap‐P. In addition, Se‐P creates a slight reversal of the timing of the atrial systoles and induces a shortening of PR interval, the extent of which could depend on the height of the pacing site on the septum. (PACE 2003; 26[Pt. I]:26–35)

Single-lead VDD pacing: long-term experience with four different systems.

BACKGROUND Previous multicenter studies have shown that single-lead VDD pacing systems provide satisfactory atrial-triggered ventricular pacing at middle term for treatment of atrioventricular block without sinus dysfunction. However, we lack data on long-term results obtained with different VDD systems implanted in a large number of patients from a single center. METHODS One hundred fifty patients (76 +/- 11 years) with second- or third-degree atrioventricular block (n = 147) or symptomatic hypertrophic cardiomyopathy (n = 3) without sinus dysfunction were paced with four different VDD pacing systems able to sense the atrium and to pace the ventricle. Atrioventricular synchronization was assessed during follow-up by ECG and Holter monitoring. RESULTS Mean value of the atrial electrogram during implantation was 2.01 +/- 0.94 mV without any differences among the four systems. With a mean follow-up of 24 +/- 11 months, 95% of patients remain paced in VDD mode, whereas 5% have been reprogrammed in VVI or VVIR mode for permanent atrial fibrillation or loss of atrial sensing; 96% of patients with sinus atrium have atrioventricular synchronization >90% and 94% of patients have >95%, without significant difference between the four systems used. CONCLUSIONS These different single-lead VDD systems can provide satisfactory long-term atrioventricular synchronization; results are comparable to those obtained with conventional DDD pacing systems with two leads.

Temporary transvenous VDD pacing as a bridge to permanent pacemaker implantation in patients with sepsis and haemodynamically significant atrioventricular block

AIMS Permanent pacemaker (PM) implantation is temporarily contraindicated in patients (pts) with sepsis. In patients with symptomatic atrioventricular (AV) block and infection, prolonged VVI pacing is therefore usually ensured by a ventricular pacing lead (PL) connected to an external PM generator. In patients with normal sinus function and heart failure, the VVI mode can exacerbate haemodynamic dysfunction. A single AV PL can be attractive to achieve physiological pacing. This study was designed to assess the efficacy and safety of temporary VDD pacing as a bridge to permanent PM implantation in patients with complete AV block until control of infection. METHODS AND RESULTS This study included eight patients with complete AV block and sepsis with negative blood culture. Due to the presence of congestive heart failure, a single bipolar AV PL connected to an external VDD PM generator. At VDD implantation, P-wave amplitude was 1.9 ± 1.6 mV and R-wave was 11.3 ± 5.2 mV. The ventricular pacing threshold was 0.53 ± 0.1 V for a 0.5 ms pulse. Antibiotic therapy was instituted in all patients. A permanent VDD or DDD PM was implanted after 8 ± 2.5 days of temporary VDD pacing. At permanent PM implantation, the mean brain natriuretic peptide level had decreased and sepsis was controlled in all patients. No recurrence of sepsis was observed with a mean follow-up of 15.8 ± 5.3 months. CONCLUSION Temporary VDD pacing is a safe and effective method to achieve prolonged AV physiological pacing in patients with AV block until infection has been controlled.

Comparative value of Doppler echocardiography and cardiac catheterization in the decision to operate on patients with aortic stenosis

With the use of Doppler echocardiography, severity of valvular stenosis, etiology and type of valve lesions, and left ventricular function can be assessed accurately in patients with aortic stenosis. The purpose of this study was to compare the value of noninvasive clinical and Doppler echocardiographic findings, with cardiac catheterization, in the management decision-making for patients with aortic stenosis. One hundred and seventy consecutive patients with aortic stenosis who underwent cardiac catheterization and Doppler echocardiography were prospectively studied. A decision to operate, not operate or remain uncertain was made independently by experienced cardiologists given clinical information in combination with either Doppler echocardiographic (group I) or cardiac catheterization (group II) data. The severity of aortic stenosis agreed between Doppler echocardiography and cardiac catheterization in 168 patients (98.8%), and disagreed in two patients. There was agreement on clinical decision to operate or not operate between Group I and Group II in 160 patients (94.1%) and a discrepant decision in only two patients (1.1%). In eight patients (4.7%) with poor echogenecity or with discordance between clinical and echocardiographic data, the decision made by group I remained uncertain. We conclude that in a large majority of patients with aortic stenosis, Doppler echocardiographic assessment provides the same management decision reached by cardiac catheterization findings.

Relationship between New York Heart Association class change and ventricular tachyarrhythmia occurrence in patients treated with cardiac resynchronization plus defibrillator

AIMS In patients with advanced heart failure (HF) and prolonged QRS interval, cardiac resynchronization therapy (CRT) reduces symptoms and risk of death. The added benefit of an implantable cardioverter defibrillator (ICD) remains questionable in some patients. METHODS AND RESULTS In 332 HF patients treated with CRT-D (CRT with ICD) [65 +/- 10 years, 86% men, 23% New York Heart Association (NYHA) class II, 65% class III, and 11% class IV, 70% primary prevention, 55% ischaemic cardiomyopathy, left ventricular ejection fraction 25 +/- 7.5%, and QRS width 167 +/- 32 ms], we evaluated the relationship between functional status change, death at 6-month follow-up (FU), and the occurrence of ventricular tachyarrhythmia/ventricular fibrillation (VT/VF). A total of 68 patients (20.5%) experienced 1266 spontaneous episodes of VT/VF during FU. There was no difference in baseline characteristics between patients with or without VT/VF, except for ICD indication (primary or secondary prevention). Improvement in NYHA class was significantly associated with a decreased occurrence of VT/VF (P = 0.004). Sixteen patients who died had significantly more often VT/VF than the survivors (50 vs. 19%, P = 0.007). CONCLUSION Within the initial 6-month post-CRT therapy, 20% of patients received an appropriate ICD therapy. Patients improving on NYHA class (responders to CRT) have less VT/VF episodes than non-responders. Discriminant criteria for CRT response are awaited to optimize the choice of the device (CRT alone, defibrillator alone, or CRT-D).

Electrocardiogram, Echocardiography, and Magnetic Resonance Imaging Characteristics in Uhl’s Disease

Uhl’s disease is a very rare affection that was originally described in 19521; few cases have been reported in the literature. It is caused by isolated right ventricular enlargement and failure with partial or total absence of right ventricular myocardium. It was first considered to be a congenital development failure in the human embryo in its early stages. However, more recent publications incriminate apoptotic anomalies for right ventricular muscle agenesy.2–3 Surgical correction has been attempted, without success.4 Cardiac transplantation may be proposed when patients become …

Predictors for short-term progressive heart failure death in New York Heart Association II patients implanted with a cardioverter defibrillator—the EVADEF study

BACKGROUND Sudden cardiac death (SCD) is the predominant cause of mortality in patients with mild heart failure (HF). This 2-year follow-up, multicenter, cohort study aimed to assess the extent to which implantable cardioverter defibrillators (ICDs), by reducing SCD, lead to predominant progressive HF death in mildly symptomatic HF patients at baseline in daily medical practice. METHODS Between June 2001 and June 2003, 1,030 New York Heart Association II patients received an ICD in 22 French centers. Sudden cardiac death and progressive HF mortality rates were assessed using competing risk methodology, and predictors for progressive HF at baseline were tested in a multivariate regression model. RESULTS During a mean follow-up of 22 +/- 6 months, 114 deaths occurred: 12 (10.5%) due to SCD and 52 (45.6%) due to progressive HF (24-month cause-specific mortality rates of 1.2% [95% CI 0.6-1.9] and 5.4% [95% CI 4.0-6.8], respectively). Diuretics use (hazard ratio [HR] 2.8, 95% CI 1.5-5.5, P = .002), history of atrial fibrillation (HR 2.09, 95% CI 1.2-3.65, P = .01), and low ejection fraction (HR 2.7, 95% CI 1.4-4.8, P = .0008) were independent predictors for progressive HF death, whereas beta-blocker therapy was a protector (HR 0.6, 95% CI 0.3-0.9, P = .04). Half of the patients (48%) who died from progressive HF within 2 years of ICD implant initially presented with enlarged QRS (> or =120 milliseconds). CONCLUSIONS Because of ICD efficiency, progressive HF is the main cause of death within 2 years of implant, although these patients are only mildly symptomatic at implantation. In addition to optimal pharmacologic therapy, these results raise the question of systematically implanting ICDs with cardiac resynchronization therapy in patients with electrical asynchronism at baseline.

Implantable cardiac defibrillator among adults with transposition of the great arteries and atrial switch operation: case series and review of literature.

BACKGROUND The experience with the implantable cardiac defibrillator (ICD) in patients with transposition of the great arteries (TGA) and history of atrial switch surgery remains limited. METHODS Retrospective evaluation aiming to assess characteristics and outcomes of consecutive TGA patients with history of atrial switch surgery implanted with an ICD between January 2005 and June 2012 in four French centers. RESULTS Of the 12 patients (median 34 years [28, 40]; 67% male), 4 patients (33%) were implanted for secondary prevention after symptomatic documented sustained ventricular tachycardia or sudden cardiac arrest. ICDs were implanted for primary prevention in 8 patients (67%), including cardiac resynchronization in 3 patients; severe systemic ventricle dysfunction was present in all cases (median ejection fraction 27% [20, 40]). Overall, one patient died during the ICD implantation secondary to refractory cardiac arrest after defibrillation testing. Over a median follow-up of 19 months [10, 106], 6 patients out of 11 (54%) experienced worsening of congestive heart failure, including 5 who were eventually transplanted. Overall, 3 patients (27%) experienced significant ICD-related complications, whereas only one patient (primary prevention indication) developed appropriate ICD therapy (successful anti-tachycardia pacing without shock). Half of the patients presented with at least one episode of sustained (≥ 5 min) atrial arrhythmia during follow-up. CONCLUSIONS Our findings underline the key role of progressive heart failure in dictating outcomes among TGA patients with prior atrial switch repair. Our results also underline the need of better risk-stratification for sudden cardiac death in those patients.

Fibrillation atriale : le plus fréquent des troubles du rythme

The incidence of atrial fibrillation increases rapidly with population age. Atrial fibrillation essentially presents a problem of long-term management. Strategies of rhythm or rate control should be considered on a case-by-case basis for each individual. Anticoagulation treatment is indicated in most cases. Radiofrequency ablation by pulmonary vein isolation is an unquestionably innovative treatment but is reserved for selected patients.

T-wave oversensing during exercise one year after cardioverter defibrillator implantation for Brugada syndrome

A 56-year-old man was hospitalized for a recent episode of syncope. The electrocardiogram (ECG) revealed a permanent type-I Brugada syndrome (figure 1). An electrophysiological study induced ventricular fibrillation. A Saint Jude Medical Atlas VR defibrillator was implanted connected to a double defibrillation coil “true” bipolar lead. The R-wave amplitude was 16 mV, the threshold stimulation 0.6 V, and the threshold of defibrillation was less than 15 J. One year later, several shocks occurred during the patient’s normal daily activities. The R-wave amplitude was 7 mV. Although no oversensing was noted at rest, stored endocardial electrograms revealed inappropriate shocks due to Twave oversensing (figure 2). An exercise stress test reproduced T-wave oversensing (figure 3), with a reduction in Rwave and an increase in T-wave amplitudes responsible for double counting of ventricular activity. No lead dislodgment was observed on chest X-ray. A reprogramming of “starting threshold” and “decay delay” suppressed T-wave oversensing during an exercise stress test. However, induced ventricular fibrillation showed undersensing of ventricular activity. Repositioning of the defibrillation lead was attempted without success due to adherences of the proximal coil. Therefore a ventricular lead for sensing and pacing was positioned at a distance of the defibrillation lead. The R-wave amplitude was then 12 mV. A new exercise stress revealed no T wave oversensing. There was no undersensing during an induced ventricular fibrillation. At 1 year, there was neither inappropriate shock nor T wave oversensing during exercise stress test. We conclude that T-wave oversensing should be suspected in Brugada syndrome because of spatial and temporal variations in the T wave. We suggest that a physical exercise test should be performed systematically and repeatedly for these patients after implantation of a cardioverter defibrillator.