Patients with mitral valve prolapse may present with chest pain and dyspnea. Left ventricular hemodynamics as a cause for these symptoms have not been completely evaluated in these patients. The present study was undertaken to investigate left ventricular hemodynamics in symptomatic patients with mitral valve prolapse. One hundred and three patients with mitral valve prolapse (female 72, male 31, age 56 +/- 11 years) had diagnostic cardiac catheterization for evaluation of chest pain (n = 44), dyspnea (n = 10) and for chest pain plus dyspnea (n = 49). All patients had diagnostic auscultatory findings and angiographic documentation of mitral valve prolapse. Patients with coronary artery disease and mitral regurgitation greater than mild were excluded from the study. Left ventricular end diastolic pressures before (chest pain 9.3 +/- 3.7 mmHg; dyspnea 8.2 +/- 4.2 mmHg; chest pain plus dyspnea 9.3 +/- 4.1 mmHg) and after left ventriculography (chest pain 11.6 +/- 5.5 mmHg; dyspnea 10.2 +/- 2.3 mmHg; chest pain plus dyspnea 11.7 +/- 5.6 mmHg) were normal in the majority of patients and similar in all three groups. Likewise, the left ventricular end diastolic volume index (chest pain 72.0 +/- 16 cm3, dyspnea 69.1 +/- 20 cm3, chest pain plus dyspnea 70.0 +/- 16 cm3) and ejection fraction (chest pain 64.0 +/- 8.4%, dyspnea 64.1 +/- 6.1%, chest pain plus dyspnea 64.3 +/- 6.1%) were normal in the majority of patients and similar in the three groups. Symptomatic patients with mitral valve prolapse without significant mitral regurgitation had normal left ventricular hemodynamics, and their symptoms cannot be explained on the basis of hemodynamic abnormalities alone.