New-onset orthostatic intolerance following bariatric surgery.

BACKGROUND: As bariatric surgery has become an increasingly popular treatment for obesity, we have seen an increasing number of patients present after bariatric surgery with new-onset syncope, near-syncope, and lightheadedness. METHODS: We retrospectively reviewed patients who had had bariatric surgery referred to our institution for evaluation of orthostatic intolerance. We reviewed history, physical examination, type of bariatric surgery procedure, and tilt table test results in these patients. There were 14 women and one man with mean age 42 +/- 6 years, preoperative body mass index was 49.3 +/- 6.0 kg/m(2), and mean postoperative weight loss was 55.9 kg. Mean onset of symptoms was 5.2 +/- 3.9 months after surgery. Presenting symptoms were lightheadedness in 15 (100%), near-syncope in 11 (73%), and syncope in nine (60%). All but one patient had a positive tilt table test with eight (53%) having a neurocardiogenic response, three (20%) having a dysautonomic response, and (20%) having a postural tachycardia response. The likely mechanism of orthostatic intolerance is autonomic insufficiency in combination with reverse course of obesity-related hypertension. The majority of the patients (12 out of 15) responded to standard therapy for autonomic insufficiency. CONCLUSION: Some patients may develop significant orthostatic intolerance due to autonomic insufficiency following bariatric surgery, and awareness of the potential association between bariatric surgery and new orthostatic intolerance is important for providing timely care.

A practical approach to the echocardiographic evaluation of diastolic function.

A number of recent community-based epidemiologic studies suggest that 40% to 50% of the cases of heart failure have preserved left ventricular systolic function. Although diastolic heart failure is often not well clinically recognized, it is associated with marked increases in morbidity and all-cause mortality. Doppler echocardiography has emerged as the principal clinical tool for the assessment of left ventricular diastolic function. Doppler mitral inflow velocity-derived variables remain the cornerstone of the evaluation of diastolic function. Pulmonary venous Doppler flow indices and mitral inflow measurements with Valsalva's maneuver are important adjuncts for differentiating normal and pseudonormal mitral inflow patterns. Unfortunately, these Doppler flow variables are significantly influenced by loading conditions and, therefore, the results from these standard techniques can be inconclusive. Recently, color M-mode and Doppler tissue imaging have emerged as new modalities that are less affected by preload and, thus, provide a strong complementary role in the assessment of diastolic function. This review will discuss the diastolic properties of the left ventricle, Doppler echocardiographic evaluation, and grading of diastolic dysfunction.