Hypertrophic cardiomyopathy natural history
Editors-In-Chief: C. Michael Gibson, M.S., M.D. [1], Cafer Zorkun, M.D. [2], Caitlin J. Harrigan [3], Martin S. Maron, M.D., and Barry J. Maron, M.D.
Sudden Cardiac Death
The incidence of sudden cardiac death (SCD) in patients with HCM is 2 to 4 percent per year in adults, and a 4 to 6 percent per year in children and adolescents[1].
Among end stage patients with a left ventricular ejection fraction < 50%, the risk of SCD over 5 years may be as high as 47%. In this population, syncope has been identified as an independent correlate of sudden cardiac death (hazard ratio = 6.15; 95% confidence interval, 2.40-15.75; P < .001)[2].
A review of 78 patients with HCM who died suddenly or survived a cardiac arrest episode showed that 71 percent were younger than 30 years of age, 54 percent were without functional limitation, and 61 percent were performing sedentary or minimal physical activity at the time of cardiac arrest.
Predictors of Sudden Cardiac Death
There are few predictors of SCD in patients with HCM.
- Onset of symptoms in childhood
- A clinical history of spontaneous, sustained monomorphic ventricular tachycardia (VT) or sudden death in family members.
- History of impaired consciousness
- Syncope
- Atrial arrhythmias
- Development of systolic dysfunction
- Non-sustained ventricular tachycardia (NSVT) in patients with symptoms
- Left ventricular wall thickness >30 mm. A recent report of 480 patients showed that left ventricular wall thickness was useful in identifying patients at high risk for sudden cardiac death. However, sudden cardiac death can occur in children and adolescents in the absence of left ventricular hypertrophy as well.
Prognosis in Survivors of Sudden Cardiac Death
Survivors of SCD have a poor prognosis. Event free survival at 1,5 and 10 years was 83, 65 and 53 percent respectively.
References
- ↑ Elliott PM, Poloniecki J, Dickie S, Sharma S, Monserrat L, Varnava A; et al. (2000). "Sudden death in hypertrophic cardiomyopathy: identification of high risk patients". J Am Coll Cardiol. 36 (7): 2212–8. PMID 11127463.
- ↑ Kawarai H, Kajimoto K, Minami Y, Hagiwara N, Kasanuki H (2011). "Risk of sudden death in end-stage hypertrophic cardiomyopathy". J Card Fail. 17 (6): 459–64. doi:10.1016/j.cardfail.2011.01.015. PMID 21624733.