[Clinical characteristics and cardiac events in elderly patients with apical hypertrophic cardiomyopathy]

Impact of coronary artery anatomy on clinical course and prognosis in apical hypertrophic cardiomyopathy: analysis of coronary angiography and computed tomography

Background and Objectives

Apical hypertrophic cardiomyopathy (AHCM) is an uncommon variant of hypertrophic cardiomyopathy with a relatively benign course. However, the prognostic factors of AHCM-particularly those associated with coronary artery disease (CAD) and its anatomical subtypes-are not well known.

Subjects and Methods

We enrolled 98 consecutive patients with AHCM who underwent coronary angiography or coronary computed tomography scanning at two general hospitals in Korea from January 2002 to March 2012. Patient charts were reviewed for information regarding cardiovascular (CV) risk factors, symptoms, and occurrence of CV events and/or mortality. We also reviewed echocardiographic data and angiography records.

Results

The mean age at the time of enrollment was 61.45±9.78 years, with female patients comprising 38.6%. The proportions of mixed and pure types of AHCM were 34.4% and 65.6%, respectively. CAD was found in 31 (31.6%) patients. The mean follow-up period was 53.1±60.7 months. CV events occurred in 22.4% of patients, and the mortality rate was 5.1%. The mixed-type was more frequent in CV event group although this difference was not statistically significant (50% vs. 30%, p=0.097). The presence of CAD emerged as an independent risk factor for CV events in univariate and multivariate Cox regression analysis after adjusting for other CV risk factors.

Conclusion

Coronary artery disease is an independent risk factor for CV events in AHCM patients. However, AHCM without CAD has a benign natural course, comparable with the general population.

Apical hypertrophic cardiomyopathy presenting as recurrent unexplained syncope

Apical hypertrophic cardiomyopathy (AHC) is a rare variant of hypertrophic cardiomyopathy. Since its description by Sakamoto in 1976 in Japanese patients, our understanding of this entity has evolved. Although cardiac magnetic resonance imaging has emerged as the gold standard for diagnosing AHC, clinical attention must be drawn to the unique electrocardiographic features that provide the initial clues to making the diagnosis. In this case, we present a 47-year-old man with AHC who presented with recurrent syncope, but anomalies on his electrocardiogram went unnoticed on two clinical encounters. He was subsequently admitted to our service and rapidly diagnosed after we observed the very classical findings in the plain twelve lead electrocardiogram done at the time of admission. In a clinical encounter involving a patient presenting with recurrent syncope, special attention must be focused on the electrocardiogram to decipher the unique diagnostic features it might show.

Apical hypertrophic cardiomyopathy

We describe a patient with asymptomatic apical hypertrophic cardiomyopathy (AHCM) who later developed cardiac arrhythmias, and briefly discuss the diagnostic modalities, differential diagnosis and treatment option for this condition. AHCM is a rare form of hypertrophic cardiomyopathy which classically involves the apex of the left ventricle. AHCM can be an incidental finding, or patients may present with chest pain, palpitations, dyspnea, syncope, atrial fibrillation, myocardial infarction, embolic events, ventricular fibrillation and congestive heart failure. AHCM is frequently sporadic, but autosomal dominant inheritance has been reported in few families. The most frequent and classic electrocardiogram findings are giant negative T-waves in the precordial leads which are found in the majority of the patients followed by left ventricular (LV) hypertrophy. A transthoracic echocardiogram is the initial diagnostic tool in the evaluation of AHCM and shows hypertrophy of the LV apex. AHCM may mimic other conditions such as LV apical cardiac tumors, LV apical thrombus, isolated ventricular non-compaction, endomyocardial fibrosis and coronary artery disease. Other modalities, including left ventriculography, multislice spiral computed tomography, and cardiac magnetic resonance imagings are also valuable tools and are frequently used to differentiate AHCH from other conditions. Medications used to treat symptomatic patients with AHCM include verapamil, beta-blockers and antiarrhythmic agents such as amiodarone and procainamide. An implantable cardioverter defibrillator is recommended for high risk patients.

Unusual features of apical hypertrophic cardiomyopathy

Apical hypertrophic cardiomyopathy (HC) is commonly regarded as a relatively benign condition of young to middle-aged Japanese men. Apical HC in a predominantly Caucasian population is not well characterized. The cardiovascular characteristics, morbidity, and mortality of a series of elderly, predominantly Caucasian subjects with apical HC are described. Thirty-two consecutive patients with apical HC (mean age 71 years, 15 men) were identified from a teaching hospital without a specialized HC clinic. Twenty-three subjects were Caucasian, 8 were Asian, and none Japanese. Twenty-two patients had coexistent hypertension. Six patients had documented late evolution of apical HC on electrocardiography and echocardiography up to 5 years after previous documented normal left ventricular morphology on echocardiography. The diagnosis of apical HC was initially missed in 7 patients because of inadequate image quality of the left ventricular apex and a lack of awareness of the condition. The correct diagnosis was assigned to all 7 patients after repeat echocardiography. Six of 13 patients who underwent coronary angiography had associated coronary artery fistulae. One patient required an implantable defibrillator for exertional syncope. Ten of the patients developed atrial fibrillation, 6 of whom had complicating thromboembolic events. Of the 6 deaths in the cohort, 2 followed atrial fibrillation-related hemiplegic strokes, and 2 followed progressive heart failure. In conclusion, apical HC in a teaching hospital without a specialized HC clinic and in a predominantly Caucasian population is a disease of the elderly. Documented late morphologic evolution is not uncommon, with a high incidence of coronary fistulae and morbid atrial fibrillation.

Myocardial thallium defects in apical hypertrophic cardiomyopathy are associated with a benign prognosis. Thallium defects in apical hypertrophy

BACKGROUND

We investigated whether myocardial thallium-201 defects in patients with apical hypertrophic cardiomyopathy are associated with an unfavorable clinical outcome, and additionally compared the presence of defects to echocardiography and angiography findings.

METHODS

Dipyridamole thallium-201 single photon emission tomography was performed in 26 apical hypertrophic cardiomyopathy patients, aged 41-78 (22 men, 6 women). Patients with or without perfusion defects were compared for echocardiographic measurements of wall thickness, chamber dimensions, and fractional shortening. Twelve patients underwent coronary angiography. The occurrence of cardiac events was evaluated during clinical follow-up for a mean period of 4.3 +/- 1.9 years (range: 1.0-7.0 year).

RESULTS

Thirteen patients (50%) showed perfusion defects, which were predominantly reversible (fixed in 1) and mostly apical (9 of 13). Patients with and without defects did not differ in symptoms, EKG findings, echocardiographic morphology or fractional shortening (41 +/- 4 vs. 41 +/- 7%). Coronary angiography was normal in all patients in whom it was performed (nine with and three without defects). During follow-up, there were no deaths or myocardial infarction. Of the defect positive group, one case developed paroxysmal supraventricular tachycardia, and another had a cerebrovascular accident. Of the defect negative group, one case developed sick sinus syndrome, while another had a hospital admission for anginal pain.

CONCLUSIONS

While reversible thallium defects in the absence of coronary artery disease occur frequently in patients with apical hypertrophic cardiomyopathy, the prognosis remains benign despite the presence of ischemia and there is no evidence for an association with adverse patient outcome.

Transient ischemic attack with apical hypertrophic cardiomyopathy

A 66-year-old Turkish male patient admitted to our emergency department with a transient ischemic attack (TIA) is described. Transthoracic echocardiography revealed apical hypertrophic cardiomyopathy (HCM) and an ECG sinus rhythm. Transesophageal echocardiography detected severe spontaneous echocontrast (SEC) in the left atrial (LA) cavity with apical hypertrophy.

Long-term outcome in patients with apical hypertrophic cardiomyopathy

OBJECTIVES

The aim of this study was to describe long-term outcome in patients with apical hypertrophic cardiomyopathy (ApHCM) followed in a tertiary referral center.

BACKGROUND

Apical hypertrophic cardiomyopathy is a relatively rare form of hypertrophic cardiomyopathy (HCM), first described in Japan. Initial reports, based on a limited number of patients, emphasized the benign nature of this condition.

METHODS

A retrospective study of 105 patients with ApHCM diagnosed at the Toronto General Hospital from 1975 to 2000 was performed. Symptoms, clinical findings, mortality and cardiovascular morbidity were analyzed.

RESULTS

The mean age at presentation was 41.4 +/- 14.5 years. During a mean follow-up of 13.6 +/- 8.3 years from presentation, cardiovascular mortality was 1.9% (2/105) and annual cardiovascular mortality was 0.1%. Overall survival was 95% at 15 years. Thirty-two patients (30%) had one or more major morbid events, the most frequent being atrial fibrillation (12%) and myocardial infarction (10%). Probability of survival without morbid events was 74% at 15 years. Three predictors of cardiovascular morbidity were identified: age at presentation <41 years, left atrial enlargement, and New York Heart Association (NYHA) class > or = II at baseline. Forty-four percent of the patients were asymptomatic at the time of last follow-up.

CONCLUSIONS

Apical hypertrophic cardiomyopathy in North American patients is not associated with sudden cardiac death and has a benign prognosis in terms of cardiovascular mortality. Nevertheless, one third of these patients experience serious cardiovascular complications, such as myocardial infarction and arrhythmias. These data are likely to influence the counseling and management of patients with ApHCM.