Interv Akut Kardiol. 2008;7(3):100-105
Hypertrophic cardiomyopathy is an autosomal dominant disease with prevalence of 0.2 % characterized mostly by asymetric hypertrophy of left ventricle (> 15 mm). Initially the cavity of the left ventricle is small and the left ventricle is hypercontractile. Obstructive form is clinically more significant (dynamic subvalvular, midventricular or apical obstruction) and according to some authors has worse prognosis. As a cause of this disease more than 200 mutations on more than 10 genes were diagnosed till now. Gregor´s or Maron´s clasification is used for the description of hypertrophic cardiomyopathy.
Symptomatology and prognosis of hypertophic cardiomyopathy is heterogenous – from asymptomatic course to sudden death. In some patients atrial fibrilation or stroke developed, but the most common symptoms are angina pectoris, effort dyspnoea or syncope. Systolic dysfunction of the left ventricle with heart failure developed in approximately 5 % of patients (burned-out phase). Mortality is estimated 1 % to 6 %. The most risky are patients with resuscitated cardiac arrest or spontaneous sustained ventricular tachycardia, patients with family history of sudden death, patients with malignant genotype, patients with unexplained syncope, patients with excessive hypertrophy of interventricular septum (> 30 mm), patients with abnormal pressure response during exercise or with nonsustained ventricular tachycardia during Holter monitoring.
Obstructive form is characterized by resting or provoked gradient > 30 mm Hg. In patients with obstructive form the risk of death is doubled, the risk of stroke or heart failure is fourtimes higher and these patients have higher risk of progression of the disease into the NYHA class III or IV. In the treatment of this disease drugs (betablockers, calcium antagonists, disopyramid), A-V sequential pacing, surgical myectomy or alcohol septal ablation are used. The most effective treatment of obstructive form are surgical myectomy and alcohol septal ablation. Surgical treatment is performed from 1960s (Morrow procedure) with low mortality (1–2 %). During long-term follow-up improvement of symptomatology, reduction of syncope frequency, better effort tolerance and reduction of left atrial diameter were seen. Alcohol septal ablation is performed from 1995 with similar mortality and with significant improvement of symptomatology in more than 90 % of patients.
Published: December 20, 2008 Show citation