Hicham El Masry

Fragmented QRS and other depolarization abnormalities as a predictor of mortality and sudden cardiac death.

Purpose of review Several invasive and noninvasive tests for risk stratification of sudden cardiac death (SCD) have been studied. Tests such as microwave T wave alternans (repolarization abnormality) and signal-averaged ECG (depolarization abnormality) have high negative predictive values but low positive predictive values in patients with heart disease. The presence of a fragmented QRS (fQRS) complex on a routine 12-lead ECG is another marker of depolarization abnormality. The purpose of this review is to discuss the potential utility of tests to detect depolarization abnormalities of the heart for the risk stratification of mortality and SCD with main emphasis on fQRS. Recent findings fQRS is associated with increased mortality and arrhythmic events in patients with coronary artery disease. fQRS has also been defined as a marker of arrhythmogenic right ventricular cardiomyopathy and Brugada syndrome. In Brugada syndrome, the presence of fQRS predicts episodes of ventricular fibrillation during follow-up. Summary fQRS may be of value in determining the risk for SCD and guiding selection for device therapy in patients with structural heart disease and Brugada syndrome. It is possible that the predictive value of fQRS for SCD can be enhanced further by combining a marker of repolarization abnormality such as microwave T wave alternans.

Does diabetes accelerate progression of calcific aortic stenosis

AIMS Calcific aortic valve stenosis (CAS) is an active disease like atherosclerosis. Effect of diabetes (D) on severity of CAS is not well documented. METHODS AND RESULTS We retrospectively analysed 166 consecutive patients with CAS and multiple echocardiograms from January 1997 to March 2005. Aortic valve area (AVA) was measured using the continuity equation. CAS severity was categorized using AVA. D and non-D patients were compared for differences in sex, hypertension, smoking, statin use using chi(2) tests. Comparisons between D and non-D for changes in AVA per year were performed using ANOVA. Study cohort included 166 males with age 70 +/- 9 years, of which 72 (43%) had D. Baseline CAS was mild in 66 subjects, moderate in 75, and severe in 25. D subjects smoked less (P = 0.02), but all other variables were similar (P > 0.05). The interaction between D and baseline CAS severity was significant (P = 0.0191), indicating comparisons should be viewed by baseline CAS severity. D had significantly larger change in AVA than non-D (P = 0.0016) for those with moderate CAS at baseline only. Adjusting for statin use did not alter the results. CONCLUSION CAS severity progresses faster in D than in non-D in subjects with moderate CAS at baseline. Statins do not affect progression of CAS.

Arrhythmogenic right ventricular dysplasia/cardiomyopathy.

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a cardiac disease characterized by fibrofatty replacement of the cardiac myocytes. Patients with ARVD/C frequently present with ventricular tachycardia and many are thought to have sudden cardiac death as the initial manifestation of the disease. Over the past decade, our understanding of the disease has increased dramatically along with delineation of the genetic basis of ARVD/C and characteristic features on diagnostic imaging. The management of patients with ARVD/C remains a challenge, especially in the light of incomplete genotype–phenotype characterization, and poor predictors of sudden cardiac death. In this article, we review the pathologic and genetic basis of ARVD/C, focusing on the diagnostic features and therapeutic challenges emerging with our enhanced knowledge of this rare disease.

Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy

Since its original description in 1994, alcohol septal ablation (ASA) has emerged as a minimally invasive modality for treatment of hypertrophic obstructive cardiomyopathy compared to surgical myomectomy. This catheter-based intervention relies on the injection of absolute alcohol into the septal perforator to induce a controlled infarction of the hypertrophied septum and consequently abolish the dynamic outflow obstruction. This gradient reduction has been correlated with a significant clinical improvement in the patient’s symptomatology and with left ventricular remodeling. The procedure has been refined throughout the years, especially with the introduction of myocardial contrast echocardiography for localization of the area at risk of infarction and the reduction in the amount of alcohol used. Major complications of ASA are uncommon in large referral centers but conduction system disturbances has been the most commonly reported complications of ASA with 10% of patients necessitating permanent pacemaker implantation for complete heart block. ASA has not been compared to the gold standard surgical myomectomy in a randomized prospective study. We review the clinical aspects of this procedure and provide some historical background.

Sudden cardiac death complicating alcohol septal ablation: a case report and review of literature.

Over the years, alcohol septal ablation has become an effective and well‐accepted modality in the treatment of patients with hypertrophic obstructive cardiomyopathy refractory to standard medical therapy. Malignant tachyarrythmias infrequently complicates the procedure and are usually self‐terminating. We describe a case of alcohol septal ablation complicated by sudden cardiac death occurring immediately following the procedure requiring prolonged resuscitative efforts with eventual complete recovery. We also discuss the pathophysiologic significance of this event in the setting of this cardiomyopathy and its relevance as a complication of the procedure.

Inflammatory aortitis with coronary arterial involvement by multidetector cardiac computed tomography

A 40-year-old man with a history of hypertension was admitted for a non-ST-segment myocardial infarction. A multidetector coronary computed tomography (MDCCT) showed proximal aortic intramural thickening with extrinsic thickening and luminal compression of the proximal left circumflex coronary artery. Subsequent surgical evaluation and positron emission tomography imaging showed evidence of active inflammation of the proximal aorta and coronary arteries. Hence, this case illustrates an uncommon cause of myocardial ischemia and the emerging complimentary role that MDCCT can play in such patients.

Rebuttal: Sudden cardiac death complicating alcohol septal ablation

It is with great interest that we read the letter by Dr Veselka outlining their experience and the outcomes of alcohol septal ablation (ASA) in their center. As emphasized in his letter, the effectiveness of ASA has been widely demonstrated in reducing the outflow gradient and favorably affecting the obstructive symptoms in patients with hypertrophic cardiomyopathy. Moreover, the procedure has been refined throughout the years and has most recently incorporated the use of echocardiographic contrast injection guidance. This guidance method has been central in defining the area at risk of infarction/ablation and potentially preventing complications such as right ventricular infarction . . . Theoretically, reducing the scar burden using this localization method might have an impact on the arrhythmogenic complications seen postprocedurally. Determining whether the arrhythmic complications seen after ASA are related to the induction of a scar, the procedure itself, or are part of the natural course of the disease is an ongoing debate. The cases that were previously reported of ventricular arrhythmias psot-ASA were variable in their time of onset and were mostly ventricular tachycardias (VT), which might very well be scar based events secondary to the iatrogenically induced infarction. To our knowledge, recurrent ventricular fibrillation has not been reported as a primary event after ASA, and it is intriguing that our case demonstrated the arrhythmia very early after her procedure favoring an ischemic basis (similar to acute MI patients). Despite following the usual protocol of localization and very slow alcohol injection, our patient manifested an usually malignant episode of VF that was difficult to terminate. This was the only case where we have encountered this problem. We agree with Dr Veselka on the importance of referral of patients with HOCM to experienced centers for performance of ASA. At such institutions an integrated approach for management and follow-up would be ideal during the peri-procedural period. The importance of identification of patients at high risk for sudden cardiac death is vital in the management of this disease. It is unknown, however, if that risk might be also predictive for ASA-associated arrhythmic events. In any case, careful consideration of the risks and benefits of the procedure are central in ensuring the safety and well-being of the patient being considered for ASA. We appreciate the confirmatory report of Dr. Veselka.