What is the clinical evidence from this study?

Study design: Observational. Population: Aortic and mitral valve disease (n=79). Intervention: Preload correction methods (systolic myocardial stiffness) vs. Conventional ejection fraction-afterload relation. Primary outcome: Assessment of myocardial contractility.

July 1, 1988Open Access

Correction for preload in assessment of myocardial contractility in aortic and mitral valve disease. Application of the concept of systolic myocardial stiffness.

Key Result

Preload correction using two new methods altered the assessment of myocardial contractility compared to conventional methods in 20-40% of patients with aortic and mitral valve disease.

Study Design

Type

Observational (n=79)

Structured PICO

Does preload correction using systolic myocardial stiffness alter the assessment of myocardial contractility compared to conventional uncorrected methods in patients with aortic and mitral valve disease?

Population

79 patients undergoing diagnostic right and left heart catheterization, including 26 with aortic stenosis, 18 with aortic insufficiency, 26 with mitral regurgitation, and 9 controls without significant coronary or cardiovascular disease.

Intervention

Assessment of myocardial contractility using two new methods that permit the correction of the ejection fraction for preload (applying the concept of systolic myocardial stiffness).

Comparator

Conventional ejection fraction-afterload relation (uncorrected for preload).

Outcome

Assessment of myocardial contractile state.surrogate

Preload correction is important in the preoperative assessment of myocardial contractility in aortic and mitral valve disease, altering the assessment in 20-40% of cases compared to conventional methods.

Abstract

With single-beat analysis, the new concept of systolic myocardial stiffness is applied to provide a new approach for the assessment of myocardial contractility in aortic and mitral valve disease. Seventy patients underwent diagnostic right and left heart catheterization. Twenty-six patients had aortic stenosis, 18 had aortic insufficiency, and 26 had mitral regurgitation. Patients with aortic stenosis were divided into two groups on the basis of left ventricular mass index less than 172 g/m2 (AS1) and mass index greater than or equal to 172 g/m2 (AS2). The mitral regurgitation patients were divided into those in normal sinus rhythm (MR1) and those in atrial fibrillation (MR2). Nine patients without significant coronary or cardiovascular disease served as controls. Thirteen patients with aortic stenosis and eight with aortic insufficiency were evaluated (average, approximately 18 months) after successful aortic valve replacement. With simultaneous left ventricular pressure and cineangiographic methods, myocardial contractility was assessed by the conventional ejection fraction-afterload relation (uncorrected for preload) and by two new methods that permit the correction of the ejection fraction for preload. Assessments of the contractile state by these two new methods differed from those by the conventional method in 20-40% of the cases studied. Contractile state improved postoperatively in aortic stenosis and aortic insufficiency even in patients with preoperative depressed contractile states. In patients with mitral regurgitation, there was considerable heterogeneity of contractile function preoperatively. Severe left ventricular hypertrophy in aortic stenosis was not a marker for postoperative outcome since contractility was normal postoperatively in AS1 and AS2 in equal numbers. This study demonstrates that preload correction is important in a preoperative assessment of contractility in aortic and mitral valve disease but that it is less important postoperatively, presumably because of reductions in the preload.