Obstructive hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a primary disease of cardiac muscle characterized by a thickening of the left ventricular wall and often predominantly affecting the interventricular septum. This paper presents a case study of a 53-year-old female with a dynamic and obstructive form of HCM. The study includes a case presentation, clinical findings, investigations, and management. Patient findings were obtained before and after alcohol septal ablation, a novel interventional therapy. The article reviews the various forms of HCM and describes the currently available treatment modalities for obstructive HCM. Further research will be necessary to determine the comparative efficacy between past, present, and future therapies.     

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 ACHM 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.     

Familial hypertrophic cardiomyopathy mimicing typical dilated cardiomyopathy

An autopsied patient who showed typical dilated cardiomyopathy (DCM)-like features and was pathologically diagnosed with hypertrophic cardiomyopathy (HCM) is presented. The patient, a 60-year-old male at the time of death, died of intractable congestive heart failure. At autopsy the heart weighed 570g and showed marked left ventricular (LV) dilatation with a thin wall (ventricular septum/free wall of the LV = 7 mm/8 mm). There was no evidence of significant stenosis in the extramural coronary arteries. Massive fibrosis was found in the middle and outer thirds of the ventricular septum and anterior wall of the LV (48% in the ventricular septum and 9% in the free wall of the LV). As myocytes were not present in the area with massive fibrosis, percent area of disarray was calculated excluding the area of massive fibrosis and found to be 30% in the ventricular septum. Based on the marked increase in the percent area of disarray, this case was diagnosed as HCM. The patient's 37-year-old son showed asymmetric septal hypertrophy on echocardiography (ventricular septum/posterior wall of the LV = 15 mm/11 mm), marked LV hypertrophy on electrocardiography, and diffuse and marked disarray by endomyocardial biopsy. There were also LV dilatation (LV diastolic dimension = 51 mm) and hypokinesis of the LV; as a result, a diagnosis of HCM with features of DCM was made.     

Treatment of hypertrophic cardiomyopathy

The treatment of hypertrophic cardiomyopathy is first and foremost symptomatic, its aim being to counteract dyspnea, angina pectoris, syncopes and lipothymias, palpitations. In therapy, use is made of beta-blockers, propranolol in particular at moderate or high doses, which are often efficacious but readily cause muscular asthenia. Calcium antagonists, especially verapamil, are a therapeutic alternative, often more efficacious but exposing the patient to the risks of iatrogenic effects which are sometimes serious and may even be fatal. Surgical myomectomy is another alternative, the functional results of which are remarkable, more often than not, but the mortality at surgery, although declining progressively, is not negligible and leads to this approach being used only in cases not responding to medical treatment as when infra-aortic septal hypertrophy is accompanied by an "obstruction". The second type of therapeutic approach is the treatment and prevention of rhythmic disorders which are an integral part of the risk of sudden death. Reduction of auricular fibrillation must play a role in the prevention of thrombo-embolic disease. Ventricular arrhythmias, especially sustained attacks of ventricular tachycardia systematically detected by ambulant ECG, ought to be prevented by anti-arrhythmics: beta-blockers, in combination or not with anti-arrhythmics of class I, amiodarone, propafenone, etc.     

Prognosis in hypertrophic cardiomyopathy

One hundred thirty-six patients with hypertrophic cardiomyopathy were followed up for 1 to 17 years. Twenty-one patients had died, 14 of them suddenly, two from heart failure, two from cerebral embolism, and three from noncardiac causes. Life table analysis revealed that sudden death was significantly associated with young age less than 20 years (relative risk [rr] = 8.63, when compared with those greater than 40 years) and with positive Master's single two-step test (rr = 3.55). Heart failure was more frequent in patients with positive Master's single test (rr = 4.27) and with left ventricular end-diastolic pressure greater than 20 mm Hg (rr = 2.58). Atrial fibrillation, observed in 15 patients, was a poor prognostic sign, resulting in five cardiac deaths and seven heart failures. In contrast, prognosis was favorable in patients with apical hypertrophy with giant negative T wave. Thus Japanese patients with hypertrophic cardiomyopathy showed a prognosis consistent with Western patients, except for excellent outcome of apical hypertrophy.