The association of chest pain, panic attack and mitral valve prolapse forms a triad which was commented upon during discussion in the recent article by Potokar and Nutt.1 Because each component of the triad is a common condition, the association of, and relationship among, these three conditions assumes an even greater clinical significance. Mitral valve prolapse is the most common disorder of the heart valve in the USA.2 It is also prevalent around the world, with prevalence varying from 1 to 38%.2 It is more frequent in young women.2 Panic attack, which has an estimated lifetime prevalence of 3% in the general population, is also more prevalent in females than in males.3 Mitral valve prolapse and panic attack often coexist.4, 5 Many studies, principally in the psychiatric literature, have suggested a significant association.6-8 Some authors consider these two conditions to be the same disease.9-11 The association of mitral valve prolapse and panic disorder may be more than co-occurrence. In fact, some authors have postulated a cause-effect relationship between the two conditions. For example, Ballenger12 suggested that mitral valve prolapse may be secondary to the increase in circulating noradrenaline and adrenaline. Rosenthal et al13 reported that mild mitral valve prolapse can be experimentally induced in the context of rapid heart rate and low ventricular volume, or by directly programmed ventricular stimulation. Decreased left ventricular end-diastolic volume is an essential feature in the pathophysiology of mitral valve prolapse.14 O'Connor and Martin15 postulated that panic attack promotes the pathological change of myxomatous degeneration seen in mitral valve prolapse, possibly through the excess catecholamines produced in panic attack.16 Whether mitral valve prolapse and panic attack are merely co-existing conditions or causally related, chest pain can be a frequent presenting symptom in both.17 The most common presenting symptom that brings the patients with mitral valve prolapse to the doctor is chest pain which may be indistinguishable from angina.18, 19 In this era of modern technology, many patients with mitral valve prolapse and chest pain, with or without associated electrocardiographic abnormalities, have often undergone sophisticated diagnostic studies including nuclear imaging and coronary arteriography, both of which are expensive and not without risk. Exercise electrocardiography which has been advocated widely as a noninvasive test for the evaluation of patients with chest pain, may be falsely positive in a patient with mitral valve prolapse, with the prevalence of an abnormal exercise electrocardiogram varying from 10 to 60%.18 The specificity of exercise electrocardiography, however, can be greatly enhanced by the prior administration of a beta-blocker. In patients with mitral valve prolapse and no coronary artery disease, a ‘positive’ exercise electrocardiogram becomes negative 1 hour after the oral administration of 40–60 mg of propranolol.20