Arrhythmic Mitral Valve Prolapse: Risk Assessment and Management.

Arrhythmic mitral valve prolapse (MVP) has gained great interest recently because of the increasing recognition of its potential role in unexplained cardiac arrest. Although evidence has accumulated to show the association of arrhythmic MVP (AMVP) with sudden cardiac death (SCD), risk stratification and management remain unclear. Physicians are faced with the challenges of screening for AMVP among MVP patients and the dilemma of when and how to intervene to prevent SCD in these patients. In addition, there is little guidance to help approach MVP patients who present with an otherwise unexplained cardiac arrest to know whether MVP was the primary cause of cardiac arrest or just an innocent bystander. Herein we review the epidemiology and definition of AMVP, the risk and mechanisms of SCD, and summarize the clinical evidence behind risk markers of SCD and therapeutic interventions that could potentially prevent it. We also propose an algorithm that provides guidance as to how to screen for AMVP and what therapeutic interventions to use. Last, we propose a diagnostic algorithm for approaching patients with otherwise unexplained cardiac arrest who are shown to have MVP.

Global, Regional, and National Burden of Calcific Aortic Valve and Degenerative Mitral Valve Diseases, 1990-2017.

BACKGROUND: Nonrheumatic valvular diseases are common; however, no studies have estimated their global or national burden. As part of the Global Burden of Disease Study 2017, mortality, prevalence, and disability-adjusted life-years (DALYs) for calcific aortic valve disease (CAVD), degenerative mitral valve disease, and other nonrheumatic valvular diseases were estimated for 195 countries and territories from 1990 to 2017. METHODS: Vital registration data, epidemiologic survey data, and administrative hospital data were used to estimate disease burden using the Global Burden of Disease Study modeling framework, which ensures comparability across locations. Geospatial statistical methods were used to estimate disease for all countries, because data on nonrheumatic valvular diseases are extremely limited for some regions of the world, such as Sub-Saharan Africa and South Asia. Results accounted for estimated level of disease severity as well as the estimated availability of valve repair or replacement procedures. DALYs and other measures of health-related burden were generated for both sexes and each 5-year age group, location, and year from 1990 to 2017. RESULTS: Globally, CAVD and degenerative mitral valve disease caused 102 700 (95% uncertainty interval [UI], 82 700-107 900) and 35 700 (95% UI, 30 500-42 500) deaths, and 12.6 million (95% UI, 11.4 million-13.8 million) and 18.1 million (95% UI, 17.6 million-18.6 million) prevalent cases existed in 2017, respectively. A total of 2.5 million (95% UI, 2.3 million-2.8 million) DALYs were estimated as caused by nonrheumatic valvular diseases globally, representing 0.10% (95% UI, 0.09%-0.11%) of total lost health from all diseases in 2017. The number of DALYs increased for CAVD and degenerative mitral valve disease between 1990 and 2017 by 101% (95% UI, 79%-117%) and 35% (95% UI, 23%-47%), respectively. There is significant geographic variation in the prevalence, mortality rate, and overall burden of these diseases, with highest age-standardized DALY rates of CAVD estimated for high-income countries. CONCLUSIONS: These global and national estimates demonstrate that CAVD and degenerative mitral valve disease are important causes of disease burden among older adults. Efforts to clarify modifiable risk factors and improve access to valve interventions are necessary if progress is to be made toward reducing, and eventually eliminating, the burden of these highly treatable diseases.

Pre-operative CT coronary angiography in patients with mitral valve prolapse referred for surgical repair: comparison of accuracy, radiation dose and cost versus invasive coronary angiography.

BACKGROUND: The aims of this study are to evaluate the accuracy of low dose multidetector computed tomography coronary angiography (MDCT) versus invasive coronary angiography (ICA) in ruling out CAD in patients with mitral valve prolapse and severe mitral regurgitation (MVP) before cardiac surgery and to compare the overall effective radiation dose (ED) and cost of a diagnostic approach in which conventional ICA should be performed only in patients with significant CAD as detected by MDCT. METHODS: Eighty patients with MVP and without history of CAD were randomized to MDCT (Group 1) or ICA (Group 2) to rule out CAD before surgery. However, ICA was also performed as gold standard reference in Group 1 to test the diagnostic accuracy of MDCT. A diagnostic work-up A in whom all patients underwent low-dose MDCT as initial diagnostic test and those with positive findings were referred for ICA was compared with work-up B in which all patients were referred for ICA according to the standard of care in terms of ED and cost. RESULTS: The two groups were homogeneous in terms of gender, age and body mass index. The overall feasibility and accuracy in a patient-based model were 99% and 93%, respectively. The overall ED and costs were significantly lower in diagnostic work-up A compared to diagnostic work-up B. CONCLUSIONS: The accuracy of low dose MDCT for ruling out the presence of significant CAD in patients undergoing elective valve surgery for mitral valve prolapse is excellent with a reduction of overall radiation dose exposure and costs.

Cross-sectional and longitudinal assessment of aortic root dilation and valvular anomalies in hypermobile and classic Ehlers-Danlos syndrome.

OBJECTIVES: To delineate the prevalence of cardiac findings in hypermobile and classic Ehlers-Danlos syndrome and provide longitudinal analysis of aortic root growth. STUDY DESIGN: A retrospective chart review was conducted, and data were analyzed for cross-sectional prevalence of aortic dilation and valvular anomalies. The clinical implications of aortic root growth were determined by assessment of progression of aortic root measurements over time and clinical symptoms. RESULTS: Patients whose first echocardiogram was obtained in late childhood or adulthood were less likely to have aortic dilation (P < .002) than those whose first echocardiogram was obtained in early childhood. Longitudinally, seven individuals had dilated aortas before age 14, and only one individual continued to show dilation after age 14 (P = .0143). No patient with a normal aortic root in childhood had development of dilation in adulthood. Fifteen of the 252 patients (6.0%) had mitral valve prolapse (MVP), although only one patient (0.4%) had MVP that was mild to moderate. CONCLUSIONS: Although aortic root size and MVP are increased in patients with these types of Ehlers-Danlos syndrome, they tend to be of little clinical consequence. Echocardiography may still be warranted as part of cardiovascular assessment, but decreased frequency of screening is recommended especially in symptom-free adults.

The economic burden of angina in women with suspected ischemic heart disease: results from the National Institutes of Health--National Heart, Lung, and Blood Institute--sponsored Women's Ischemia Syndrome Evaluation.

BACKGROUND: Coronary angiography is one of the most frequently performed procedures in women; however, nonobstructive (ie, < 50% stenosis) coronary artery disease (CAD) is frequently reported. Few data exist regarding the type and intensity of resource consumption in women with chest pain after coronary angiography. METHODS AND RESULTS: A total of 883 women referred for coronary angiography were prospectively enrolled in the National Institutes of Health--National Heart, Lung, and Blood Institute--sponsored Women's Ischemia Syndrome Evaluation (WISE). Cardiovascular prognosis and cost data were collected. Direct (hospitalizations, office visits, procedures, and drug utilization) and indirect (out-of-pocket, lost productivity, and travel) costs were estimated through 5 years of follow-up. Among 883 women, 62%, 17%, 11%, and 10% had nonobstructive and 1-vessel, 2-vessel, and 3-vessel CAD, respectively. Five-year cardiovascular death or myocardial infarction rates ranged from 4% to 38% for women with nonobstructive to 3-vessel CAD (P < 0.0001). Five-year rates of hospitalization for chest pain occurred in 20% of women with nonobstructive CAD, increasing to 38% to 55% for women with 1-vessel to 3-vessel CAD (P < 0.0001). The volume of repeat catheterizations or angina hospitalizations was 1.8-fold higher in women with nonobstructive versus 1-vessel CAD after 1 year of follow-up (P < 0.0001). Drug treatment was highest for those with nonobstructive or 1-vessel CAD (P < 0.0001). The proportion of costs for anti-ischemic therapy was higher for women with nonobstructive CAD (15% versus 12% for 1-vessel to 3-vessel CAD; P = 0.001). For women with nonobstructive CAD, average lifetime cost estimates were $767,288 (95% CI, $708,480 to $826,097) and ranged from $1,001,493 to $1,051,302 for women with 1-vessel to 3-vessel CAD (P = 0.0003). CONCLUSIONS: Symptom-driven care is costly even for women with nonobstructive CAD. Our lifetime estimates for costs of cardiovascular care identify a significant subset of women who are unaccounted for within current estimates of the economic burden of coronary heart disease.

Clinical and echocardiographic assessment of Nigerian patients seen at the Lagos University Teaching Hospital with features of mitral valve prolapse.

In a 3-year prospective echocardiographic study of patients with clinical features of mitral valve prolapse who presented to the cardiology clinic of the medical out patients clinic of the Lagos University Teaching Hospital comprising of sixty-two patients. The most common complaints found were vague chest discomfort (42%) and chest pain. (28%) Their mean body mass index was 20.8 +/- 5.56 Kg/m2. The most common auscultatory sign was apical clicks (8%). Hypertension (12%) was the most common clinical association while the anterior leaflet (87%) was more affected. Mitral regurgitation was present in 35.7% of cases, which were mostly mild in severity (93%). There were statistical differences in the chamber and wall dimension measurements of those with isolated mitral valve prolapse when compared with those associated with other clinical conditions. (p < 0.05). Subjects with isolated mitral valve prolapse were found to have significant differences in the echocardiographic measurements when compared with those with coexisting diseases suggesting that mitral valve prolapse is a relatively benign condition except coexisting with other conditions like hypertension, valvular defects and obesity. These associated conditions tended to increase cardiac risk.

Transesophageal echocardiographic assessment of systolic mitral leaflet displacement among patients with mitral valve prolapse.

Though qualitative transthoracic echocardiographic criteria for abnormal systolic leaflet motion are widely accepted as diagnostic characteristics of mitral valve prolapse, transesophageal echocardiographic criteria have not been evaluated against such a standard. Because transesophageal imaging planes are not identical to transthoracic imaging planes, validation of transesophageal echocardiographic criteria for mitral valve prolapse is needed. Eleven patients with mitral valve prolapse (based on physical findings and transthoracic echocardiographic criteria) and 11 healthy persons underwent prospective transesophageal echocardiography in two orthogonal imaging planes. Measurements of maximal leaflet displacement superior to the annular hinge points and mitral prolapse area subtended by the displaced mitral leaflets and the chord connecting the annular hinge points were performed in triplicate and averaged by a blinded observer. Though maximal systolic leaflet displacement was greater among patients with mitral valve prolapse than healthy subjects for both the transesophageal four-chamber (0.66+/-0.39 cm versus 0.05+/-0.11 cm, p < 0.001) and two chamber views (0.57+/-0.44 cm versus 0.20+/-0.25 cm, p < 0.04), no unique value differentiated patients with from those without mitral valve prolapse. Mitral prolapse area was greater for patients with mitral valve prolapse than for healthy subjects in both transesophageal four-chamber (1.23+/-1.18 cm2 versus 0.03+/-0.06 cm2, p < 0.02) and two-chamber views (1.73+/-1.65 cm2 versus 0.21+/-0.31 cm2, p < 0.02). Whereas a mitral prolapse area of 0.20 cm2 uniquely differentiated patients with from those without mitral valve prolapse in the four-chamber view, data overlap prevented determination of a similar diagnostic criterion for the two-chamber view. The difficulty in defining quantitative transesophageal echocardiographic criteria for mitral valve prolapse based on leaflet displacement alone suggested that the simple qualitative observation of leaflet displacement above the annular hinge points should not be used as a defining morphologic criterion for mitral valve prolapse.

Perspectives of the person with mitral valve prolapse syndrome: a study of self-care needs derived from a health deviation.

Epidemiological studies in the United States indicate that 5% of the population or nearly 7 million people have Mitral Valve Prolapse. This incidence has also been confirmed by British physicians. Approximately half of these persons seek medical care for treatment of symptoms. Persons with symptoms are often said to have "Mitral Valve Prolapse Syndrome." The purpose of this study was to describe experiences and self-care needs of persons diagnosed with Mitral Valve Prolapse Syndrome (MVPS). In Phase I of the study, medical records of 124 subjects were reviewed to identify the medical experience and typical symptoms associated with MVPS. In Phase II, 20 subjects with typical symptoms were interviewed using a semi-structured questionnaire based on health deviation self-care requisites developed by Orem. Results of this pilot study indicate that interviewed subjects with MVPS frequently had unresolved health concerns and were seeking help. Nursing assistance may therefore be needed to help such clients understand this health deviation, to make decisions regarding appropriate actions, and to accomplish self-care actions.

Screening for mitral valve prolapse: an analysis of benefits and costs in the U.S. Air Force.

Using the techniques of decision analysis, several possible mitral valve prolapse screening strategies for U.S. Air Force aircrew candidates are evaluated. Available clinical and epidemiological data are organized so that the relative merits of various strategies can be assessed by decision makers. The most efficient strategy is to screen pilot candidates with Quetelet's index (weight in kilograms/height in meters squared) and then eliminate those with an index at or below 15 who have an echocardiogram positive for mitral valve prolapse. The next most efficient strategy is to do echocardiograms on candidates with a heart murmur or click. Screening all candidates with an echocardiogram is much less efficient. Screening fighter pilot candidates only is a very inefficient strategy. Available data do not make a very convincing case for any screening program. Concerned and informed physicians will continue to have honest disagreements about screening for mitral valve prolapse in aircrew members.

The prevalence of mitral valve prolapse in patients with Down's syndrome: implications for dental management.

Eighty-three noninstitutionalized patients with Down's syndrome, aged 9 to 55 years, were randomly selected to receive echocardiograms. Forty-one patients had echocardiographic findings indicative of mitral valve prolapse, and 15 of these patients lacked associated auscultatory findings. Because mitral valve prolapse can predispose patients to bacterial endocarditis after bacteremia-producing dental procedures, these findings suggest that if auscultatory findings alone are used, a significant number of patients with Down's syndrome who are at risk for endocarditis may not be currently identified in the course of routine clinical practice.