Clinical Profile and Significance of Delayed Enhancement in Hypertrophic Cardiomyopathy

Abstract

Background-Contrast-enhanced cardiovascular magnetic resonance with delayed enhancement (DE) can provide in vivo assessment of myocardial fibrosis. However, the clinical significance of DE in hypertrophic cardiomyopathy (HCM) remains unresolved. Methods and Results-Cine and cardiovascular magnetic resonance with DE were performed in 202 HCM patients (mean age, 42Ϯ17 years; 71% male), DE was compared with clinical and demographic variables, and patients were followed up for 681Ϯ249 days for adverse disease events. DE was identified in 111 (55%) HCM patients, occupying 9%Ϯ11% of left ventricular myocardial volume, including Ͼ25% DE in 10% of patients. The presence of DE was related to occurrence of heart failure symptoms (Pϭ0.05) and left ventricular systolic dysfunction (Pϭ0.001). DE was present in all patients with ejection fraction Յ50% but also in 53% (102/192) of patients with preserved ejection fraction (PϽ0.001); %DE was both inversely related to (rϭϪ0.3; PϽ0.001) and an independent predictor of ejection fraction (rϭϪ0.4; PϽ0.001). DE (7%Ϯ7% of left ventricle) was present in 54 patients who were asymptomatic (and with normal ejection fraction). Over the follow-up period, the annualized adverse cardiovascular event rate in patients with DE exceeded that in patients without DE but did not achieve statistical significance (5.5% versus 3.3%; Pϭ0.5). Conclusions-In a large HCM cohort, DE was an independent predictor of systolic dysfunction but with only a modest relationship to heart failure symptoms. These data suggest an important role for myocardial fibrosis in the clinical course of HCM patients but are not sufficient at this time to consider DE as an independent risk factor for adverse prognosis.

The Effect of Diazepam on the Function of Hypertrophied Rats’ Hearts in Ischemia-Reperfusion Conditions

“…Previous studies also showed that administration of isoproterenol could lead to cardiac hypertrophy (2,20). In fact, chronic stimulation of myocardial β-receptors could induce the process of hypertrophy (21,22). Our findings also showed that administration of diazepam 1 and 5 mg/kg significantly decreased the CMI of the isoproterenol-treated groups, which revealed the preventive role of diazepam against isoprpterenol-induced cardiac hypertrophy.…”

“…This imbalance is caused by inadequate capillary density in relation to the increased myocardial mass and limitation of blood flow despite high oxygen demand of the myocardium (9,(33)(34)(35). Therefore, it could exacerbate the myocardial injury after ischemia (5,21,22). As it was expected, our findings showed the exacerbation of I/R injury in the isoproterenolinduced hypertrophied hearts.…”

Phenotypic expression in hypertrophic cardiomyopathy and late gadolinium enhancement on cardiac magnetic resonance

“…The mean age of our population (56.4±17.0 years) was older than in most studies in the literature 5,11,12 and included few patients in the age-group most associated with sudden death (<35 years). Most were asymptomatic or mildly symptomatic, as in other published series.…”

“…Maron et al 12 reported a high prevalence, although not reaching statistical significance, of cardiovascular events during follow-up of 202 patients with HCM and LGE. By contrast, in a study of 220 asymptomatic or only mildly symptomatic HCM patients with a mean follow-up of three years, Bruder et al 15 showed that LGE was an independent predictor of cardiac death (hazard ratio [HR] 8.6; p=0.038), whereas the presence of one or two clinical risk factors did not reach statistical significance (HR 1.4; p=0.68).…”

Hipertrofik kardiyomiyopatili hastaların risk sınıflandırmasında görüntüleme yöntemlerinin yeri

“…İleriye dönük bazı çalışmalarda AKÖ gelişen veya uygun ICD şoklaması alan HKM hastalarında GGT'nin daha fazla görüldüğü belirlenmiştir (44). Hipertrofik kardiyomiyopatili hastaların yaklaşık %65'inde fibrozisin kanıtı olan GGT saptanması nedeniyle GGT'nin tek başına pozitif olmasının kardiyak olayları ön görmede iyi bir parametre olamayacağını düşünülmektedir (45). Eldeki mevcut veriler bu konuda yapılmış geniş çaplı ileriye dönük çalışma yapılmamış olmasından dolayı GGT'nin AKÖ açısından tek bağımsız risk faktörü olamayacağını belirtmektedir (45).…”