Cardiomyopathy systolic function

To date, proteomic investigations into human heart disease have centered on dilated cardiomyopathy (DCM). DCM is a disease of unknown etiology, characterized by impaired systolic function resulting in heart failure. Known contributory factors of DCM are viral infections, cardiac-specific autoantibodies, toxic agents, genetic factors, and sustained alcohol abuse. As many as 100 cardiac proteins... 

Chen L, Meyers D, Javorsky G et al (2007) Arg389Gly-betal -adrenergic receptors determine improvement in left ventricular systolic function in non-ischemic cardiomyopathy patients with heart failure after chronic treatment with carvedilol. Pharmacogenet Genomics 17 941-949... 

Heart failure (HP) may becausedbya primary abnormality in systolic function, diastolic function, or both. Making the distinction is important because the prevalence, prognosis, and treatment of HP may be quite different depending on whether the predominant mechanism causing the symptoms is systolic or diastolic dysfunction. Some clinical studies have reported that as many as 30% to 50% of patients with congestive heart failure have preserved left ventricular (LV) function, making diastolic heart failure (DHP) very common. In addition, abnormalities in diastolic function also can play an important role in the development of symptoms in patients with cardiomyopathy and systolic heart failure (SHP). 

In dilated cardiomyopathy, the cardinal feature is dilatation of the ventricles. Systohc fnnction is abnormal, leading to a decreased cardiac ontpnt. Inpatients with hypertrophic cardiomyopathy (HCM), the ventricnlar cavity is not dilated, and the ventricnlar mnscle mass is increased. Ventricnlar cavity size is normal or decreased, and systolic function often is preserved. Patients with HCM may have an obstructive or nonobstructive form. Patients with restrictive cardiomyopathy have inadequate ventricular comphance causing diastolic dysfunction owing to endocardial and/or myocardial disease. The chnical presentation is similar to that of constrictive pericarditis. 

Restrictive cardiomyopathy is primarily an abnormality of diastolic function that results in impaired filling and increases in ventricular end-diastolic pressures with normal or decreased diastolic volume. It is associated with normal systolic function early in the course of the disease but a decrease in systolic function later in the disease... 

The treatment of restrictive cardiomyopathy is complex becanse of the heterogeneity of the pathophysiologic abnormalities. Dinretics are used for the symptoms of venous congestion in the presence of restrictive cardiomyopathy, but caution is advised because these patients require high filling pressures to maintain an adequate stroke volume and cardiac output. Hypotension and hypoperfusion may occur as a result of the excessive use of diuretics. Because systolic function is often normal, digoxin is of little benefit and may be proarrhyth-... 

Receptor antagonists improve symptoms, exercise tolerance, and measures of ventricular function over a period of several months in patients with heart failure due to idiopathic dilated cardiomyopathy. Serial measurements indicate that a decrease in systolic function does occur immediately after initiation of a /I antagonist in CHF patients, but systolic function recovers and improves beyond baseline levels over the ensuing 2-4 months. Improved ventricular function with chronic /3 receptor antagonist therapy may be due to attenuation or prevention of the /3 adrenergic receptor-mediated adverse effects of catecholamines on the myocardium. 

The literature includes eight case reports of pulmonary hypertension in AL amyloidosis attributed to pulmonary vascular amyloid deposition (Table 2). Autopsies confirmed pulmonary artery amyloid deposits in four out of four cases. The prevalence of restrictive cardiomyopathy and diastolic dysfunction in AL patients predisposes them to secondary forms of pulmonary vascular disease. Direct measurements of pulmonary artery pressures (PAP) were obtained in five cases (3 pulmonary arteriograms, 2 right heart catheterizations) however, only two reports include direct measures of left atrial filling pressures. Echocardio-graphic estimates of elevated right ventricular systolic pressures and normal diastolic function were reported in all cases. 

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