Cardiac arrest and ventricular tachycardia in Japanese-type apical hypertrophic cardiomyopathy

Apical hypertrophic cardiomyopathy (HCM) is a specific variant of HCM. This disease has been first described in Japan where the prevalence is much higher than in the western world. The prognosis of apical HCM with regard to sudden cardiac death is believed to be better than that of common HCM. We present, however, two male caucasian patients with apical HCM and malignant arrhythmias. Both patients had marked apical hypertrophy on echocardiography, 'giant' negative T-waves on the ECG and spade-like configuration of the left ventricle on angiography. The first patient had been successfully recussitated from cardiac arrest at the age of 52 years. The second patient had a syncope at the age of 42 years and had non-sustained ventricular tachycardia. In both cases, a cardioverter-defibrillator was implanted and treatment with verapamil was initiated. These observations suggest that the risk of sudden cardiac death might be increased not only in common HCM, but also in Japanese-type apical HCM.     

Clinical sustained uniform ventricular tachycardia in hypertrophic cardiomyopathy: association with left ventricular apical aneurysm.

Of 51 patients with hypertrophic cardiomyopathy who had episodes of ventricular tachycardia detected during ambulatory electrocardiographic monitoring only two had clinical sustained uniform ventricular tachycardia that required medical treatment because of worsening symptoms. In both patients the arrhythmia was associated with the uncommon finding of an apical aneurysm with angiographically normal coronary arteries.     

Clinical sustained uniform ventricular tachycardia in hypertrophic cardiomyopathy: association with left ventricular apical aneurysm

Of 51 patients with hypertrophic cardiomyopathy who had episodes of ventricular tachycardia detected during ambulatory electrocardiographic monitoring only two had clinical sustained uniform ventricular tachycardia that required medical treatment because of worsening symptoms. In both patients the arrhythmia was associated with the uncommon finding of an apical aneurysm with angiographically normal coronary arteries.     

Long-term outcome of patients with hypertrophic cardiomyopathy successfully resuscitated after cardiac arrest

This study describes the long-term outcome of 33 patients with hypertrophic cardiomyopathy who experienced a cardiac arrest but were successfully resuscitated. Cardiac arrest occurred at ages 9 to 62 years (mean 32); five patients survived multiple (two or three) arrests. A variety of treatments were administered; 18 patients with left ventricular outflow tract obstruction underwent ventricular septal myotomy-myectomy or mitral valve replacement and also received drug therapy; 15 patients received medical therapy alone. To date, 22 (67%) of the 33 patients have survived after the initial cardiac arrest for periods of 17 months to 22 years (mean 7 years); 12 patients have survived for greater than or equal to 5 and 6 for greater than or equal to 10 years. Of the 22 survivors, 16 have remained asymptomatic or only mildly symptomatic over the period of follow-up; 6 others have become severely symptomatic with heart failure, including 3 with evidence of left ventricular wall thinning and cavity enlargement. Eight patients ultimately died of natural cardiac causes (suddenly or of progressive heart failure) 7 months to 8.4 years (mean 4 years) after their initial cardiac arrest. Actuarial patient survival was 97 +/- 3%, 74 +/- 9% and 61 +/- 11% after 1, 5 and 10 years, respectively. Event-free rate (defined as actuarial survival without recurrent cardiac arrest of death) was 83 +/- 7%, 65 +/- 9% and 53 +/- 11%, respectively. For this group of patients with hypertrophic cardiomyopathy who were treated in a nonsystematic fashion with a variety of therapeutic strategies, the long-term outcome after surviving a cardiac arrest was variable.(ABSTRACT TRUNCATED AT 250 WORDS)     

Improved survival with amiodarone in patients with hypertrophic cardiomyopathy and ventricular tachycardia.

The effect of amiodarone on survival was assessed in patients with hypertrophic cardiomyopathy and ventricular tachycardia in a drug trial with historical controls. During 1976 and 1977, 24 hour (seven) or 48 hour (79) electrocardiographic monitoring was performed in 86 consecutive patients; 24 had ventricular tachycardia and received conventional antiarrhythmic agents. Nineteen clinical, echocardiographic, and haemodynamic features were assessed. Seven patients died suddenly during follow up of three years; of these, five had continued to have ventricular tachycardia and two had no documented ventricular tachycardia. During 1978 and 1979, ventricular tachycardia was detected during 48 hour electrocardiographic monitoring in 21 of the next 82 consecutive patients with hypertrophic cardiomyopathy. They received amiodarone (150-400 mg/day, median 300); ventricular tachycardia was suppressed in all during repeat 48 hour electrocardiographic examination. Two patients died suddenly during a three year follow up, but neither belonged to the amiodarone treated group with ventricular tachycardia. The clinical and haemodynamic variables were similar in patients taking amiodarone and conventional agents. The fact that control of ventricular arrhythmia with amiodarone is significantly associated with improved survival suggests that amiodarone may prevent sudden death in patients with hypertrophic cardiomyopathy and ventricular tachycardia.     

New-onset sustained ventricular tachycardia after cardiac surgery

BACKGROUND: The de novo occurrence of sustained ventricular tachycardia (VT) after CABG has been described, but the incidence, mortality rate, long-term follow-up, and mechanism are not well defined. METHODS AND RESULTS: This prospective study enrolled consecutive patients undergoing CABG at a single institution. Patients were followed up for the development of sustained VT, and a detailed analysis of clinical, angiographic, and surgical variables associated with the occurrence of VT was performed. A total of 382 patients participated, and 12 patients (3.1%) experienced >/=1 episode of sustained VT 4.1+/-4.8 days after CABG. In 11 of 12 patients, no postoperative complication explained the VT; 1 patient had a perioperative myocardial infarction. The in-hospital mortality rate was 25%. Patients with VT were more likely to have prior myocardial infarction (92% versus 50%, P<0.01), severe congestive heart failure (56% versus 21%, P<0.01), and ejection fraction <0.40 (70% versus 29%, P<0.01). When all 3 factors were present, the risk of VT was 30%, a 14-fold increase. Patients with VT had more noncollateralized totally occluded vessels on angiogram (1.4+/-0.97 versus 0.54+/-0.7, P<0.01), a bypass graft across a noncollateralized occluded vessel (1.50+/-1.0 versus 0.42+/-0.62, P<0.01), and a bypass graft across a noncollateralized occluded vessel to an infarct zone (1.50+/-1.0 versus 0.17+/-0.38, P<0.01). By multivariate analysis, the number of bypass grafts across a noncollateralized occluded vessel to an infarct zone was the only independent factor predicting VT. CONCLUSIONS: The first presentation of sustained monomorphic VT in the recovery period after CABG is uncommon, but the incidence is high in specific clinical subsets. Placement of a bypass graft across a noncollateralized total occlusion in a vessel supplying an infarct zone was strongly and independently associated with the development of VT.     

Verapamil-induced ventricular tachycardia in hypertrophic cardiomyopathy

A 17-year old boy with hypertrophic obstructive cardiomyopathy(HOCM) developed repeated short runs of self terminating ventriculartachycardia 12 hours after starting oral verapamil, which wassubstituted for propranolol therapy. It is suggested that alterationsin sympathetic tone induced by changing from a beta-blockerto a calcium antagonist might have increased myocardial irritabilitythus favouring genesis of severe ventricular arrhythmias. Verapamilis often considered to be more effective than propranolol inthe treatment of HOCM. However, if propranolol is replaced byverapamil one has to take account of the possibility of seriousarrhythmias as demonstrated by our case.     

Mid‐ventricular obstruction is associated with non‐sustained ventricular tachycardia in patients with hypertrophic obstructive cardiomyopathy

BackgroundMid‐ventricular obstruction (MVO) is a rare subtype of hypertrophic cardiomyopathy (HCM) but it is associated with ventricular arrhythmia. The relationship between MVO and non‐sustained ventricular tachycardia (NSVT) in HCM patients is unknown.HypothesisThe severity of MVO increases the incidence of NSVT in patients with hypertrophic obstructive cardiomyopathy (HOCM).MethodsFive hundred and seventy‐two consecutive patients diagnosed with HOCM in Fuwai Hospital between January 2015 and December 2017 were enrolled in this study. Holter electrocardiographic and clinical parameters were compared between HOCM patients with and without MVO.ResultsSeventy‐six (13.3%) of 572 patients were diagnosed with MVO. Compared to patients without MVO, those with MVO were much younger, and had a higher incidence of syncope, greater left ventricular (LV) posterior wall thickness, a higher percentage of LV late gadolinium enhancement, and higher prevalence of NSVT. Furthermore, the prevalence of NSVT increased with the severity of MVO (without, mild, moderate or severe: 11.1%, 18.2%, 25.6%, respectively, p for trend < .01). Similarly, the prevalence of NSVT differed among patients with isolated LV outflow tract (LVOTO), both MVO and LVOTO, and isolated MVO (11.1%, 21.3%, 26.6%, respectively, p for trend = .018). In addition to age, diabetes, left atrial diameter, and maximal wall thickness, multivariate analysis revealed the presence of MVO as an independent risk factor for NSVT (Odds ratio 2.69; 95% confidence interval 1.41 to 5.13, p = .003).ConclusionsThe presence and severity of MVO was associated with higher incidence of NSVT in HOCM patients.     

Sotalol for refractory sustained ventricular tachycardia and nonfatal cardiac arrest

The efficacy and safety of sotalol were assessed by electrophysiologic testing and ambulatory recordings in 16 patients with recurrent sustained ventricular tachycardia (VT) or nonfatal cardiac arrest who were refractory to an average of 4.8 conventional antiarrhythmic agents. Twenty-four-hour ambulatory recordings were performed before and after sotalol therapy. Fourteen patients underwent baseline electrophysiologic study and sustained VT was inducible in 12. Oral sotalol (320 to 960 mg/day) completely suppressed inducible sustained VT in 7 patients (58%), with modification in 3 (25%). Ventricular premature complexes were suppressed from baseline (mean +/- standard deviation) 431 +/- 616 to 60 +/- 110/hr (p less than 0.03). After a mean follow-up of 19 +/- 7 months, 12 of 14 patients receiving sotalol treatment had successful suppression of ventricular premature complexes (60 +/- 85/hr) and remained clinically free of sustained VT, except 2 who needed additional antiarrhythmic drugs to suppress the recurrent sustained VT. One patient died suddenly after 25 months of sotalol treatment. No severe side effects were noted during sotalol therapy. This study demonstrates that sotalol is a well-tolerated, effective antiarrhythmic agent in patients at high-risk for sudden death. It appears to be beneficial in patients who did not benefit from multiple drug treatment.     

Left ventricular myotomy and myectomy in patients with obstructive hypertrophic cardiomyopathy and previous cardiac arrest

Left ventricular myotomy and myectomy was carried out in nine patients with obstructive hypertrophic cardiomyopathy solely because of a previously documented episode of cardiac arrest. Before cardiac arrest, each patient had either no or only minimal functional limitation and therefore would not have met the usual criteria for operation, namely, severe symptoms unresponsive to medical therapy. Of the nine patients, one died in the perioperative period, and one died suddenly and unexpectedly 9 months postoperatively. The remaining seven patients have survived 9 months to 5.5 years after operation; six of the seven are asymptomatic and one has only mild symptoms. Operation resulted in a marked decrease or abolition of the left ventricular outflow gradient under basal conditions in seven of the eight patients studied postoperatively. Significant residual outflow obstruction was demonstrated after operation in the patient who later died.Sudden death in patients with obstructive hypertrophic cardiomyopathy appears usually to result from ventricular arrhythmia, and prevention of recurrent fatal arrhythmia is the goal of treatment in patients who have had cardiac arrest and have been resuscitated. Such patients should be treated indefinitely with antiarrhythmic drugs. In addition, when severe outflow obstruction is present, we postulate that effective operative relief of obstruction and consequent reduction of left ventricular systolic pressure will provide additional protection.     

Sustained ventricular arrhythmias: differences between survivors of cardiac arrest and patients with recurrent sustained ventricular tachycardia

Clinical, angiographic, echocardiographic and electrophysiologic data were examined in 101 patients with a history of sustained ventricular arrhythmia not associated with acute myocardial infarction. These patients included 66 survivors of out of hospital cardiac arrest and 35 patients presenting with hemodynamically well tolerated sustained ventricular tachycardia. On univariate analysis, patients in the cardiac arrest group had a lower incidence of previous myocardial infarction and left ventricular aneurysm and a higher ejection fraction compared with the ventricular tachycardia group. During electrophysiologic testing, the arrhythmia induced in the patients in the cardiac arrest group was fast and polymorphic and frequently degenerated into ventricular fibrillation. In contrast, in the ventricular tachycardia group, a slower, monomorphic and hemodynamically well tolerated ventricular tachycardia was commonly induced. On multivariate analysis, a polymorphic pattern of the induced ventricular arrhythmia was the only independent variable that distinguished the survivors of cardiac arrest from those presenting with sustained ventricular tachycardia. These results suggest that 1) the survivors of cardiac arrest and patients presenting with sustained well tolerated ventricular tachycardia are clinically distinct groups; and 2) the polymorphic tachycardia induced during programmed electrical stimulation in the survivors of cardiac arrest may indicate an unstable tachycardia mechanism. This may explain why these patients present with ventricular fibrillation and cardiac arrest, whereas others present with hemodynamically stable ventricular tachycardia.     

Programmed electrical stimulation in hypertrophic cardiomyopathy. Results in patients with and without cardiac arrest or syncope

Programmed electrical stimulation was performed in 54 consecutivepatients with hypertrophic cardiomyopathy. There were 11 ‘symptomatic’patients: three had a history of cardiac arrest due to ventriculartachyarrhythmias (group A), and eight had a history of syncopeof unknown origin (group B); 43 patients were ‘asymptomatic’,i.e. they had no documented or suspected symptomatic ventriculararrhythmias (group C). There were no differences among the groupswith respect to electrocardiographic, echocardiographic or hemodynamicdata. Ventricular arrhythmias were induced by atrial and rightand left ventricular stimulation with a maximum of two extrastimuliin 18 patients. Induced arrhythmias were repetitive ventricularresponse in six patients, nonsustained ventricular tachycardiain four, sustained ventricular tachycardia in five, and ventricularfibrillation in three patients. With one exception, ventriculartachycardia was always rapid (cycle lengths ranged from 180to 250 ms); it was polymorphic in six patients and monomorphicin three. Atrial stimulation induced rapid monomorphic ventriculartachycardia in one group A patient. The type and incidence ofinduced ventricular arrhythmias did not differ among the threegroups. It is concluded that programmed electrical stimulationinduces the same type of ventricular arrhythmia (rapid polymorphicventricular tachycardia or ventricular fibrillation) in ‘symptomatic’and ‘asymptomatic’ patients with hypertrophic cardiomyopathy,the incidence in the latter group being 19%. Induction by atrialstimulation of a rapid ventricular tachycardia may be a specificfinding to identify patients with hypertrophic cardiomyopathyat risk for exercise-induced ventricular fibrillation.     

Improved survival with amiodarone in patients with hypertrophic cardiomyopathy and ventricular tachycardia

The effect of amiodarone on survival was assessed in patients with hypertrophic cardiomyopathy and ventricular tachycardia in a drug trial with historical controls. During 1976 and 1977, 24 hour (seven) or 48 hour (79) electrocardiographic monitoring was performed in 86 consecutive patients; 24 had ventricular tachycardia and received conventional antiarrhythmic agents. Nineteen clinical, echocardiographic, and haemodynamic features were assessed. Seven patients died suddenly during follow up of three years; of these, five had continued to have ventricular tachycardia and two had no documented ventricular tachycardia. During 1978 and 1979, ventricular tachycardia was detected during 48 hour electrocardiographic monitoring in 21 of the next 82 consecutive patients with hypertrophic cardiomyopathy. They received amiodarone (150-400 mg/day, median 300); ventricular tachycardia was suppressed in all during repeat 48 hour electrocardiographic examination. Two patients died suddenly during a three year follow up, but neither belonged to the amiodarone treated group with ventricular tachycardia. The clinical and haemodynamic variables were similar in patients taking amiodarone and conventional agents. The fact that control of ventricular arrhythmia with amiodarone is significantly associated with improved survival suggests that amiodarone may prevent sudden death in patients with hypertrophic cardiomyopathy and ventricular tachycardia.     

Apical hypertrophic cardiomyopathy and ventricular tachycardia

Apical hypertrophic cardiomyopathy was originally reported fromJapan as one of the subsets of hypertrophic cardiomyopathy withoutgradient, usually associated with deep T-wave inversion anda spade-like appearance of the left ventricle. Although manyreports from Japan have indicated that these patients with apicalhypertrophic cardiomyopathy are mostly asymptomatic and haverelatively good prognosis, data on serious ventricular arrhythmiasare not yet available. Present documentation of ventriculartachycardia in a patient with this disease suggests that atleast some of such patients are also at risk of sudden deathand that a systematic study for life-threatening arrhythmiaby ambulatory electrocardiographic monitoring may be necessaryin these cases.