Sims, Jason R.

Objective A subset of patients at the time of transcatheter mitral valve repair (TMVR) will have normal left atrial pressure (LAP) (<13 mm Hg) despite having severe mitral regurgitation (MR). The goal of this study was to determine clinical characteristics and outcomes in patients with normal LAP undergoing TMVR. Methods A single-centre retrospective cohort of consecutive patients who underwent transcatheter edge-to-edge mitral valve clip and continuous LAP monitoring between 5/1/2014 and 5/1/2018 was analysed. One-year mortality was compared by Kaplan–Meier survival curves. Multivariable analysis was performed to identify predictors of normal LAP and 1 year mortality. Results Of the 204 patients undergoing TMVR, 65% were men and the mean age was 81. Of these patients, 31 (15%) had normal LAP (mean LAP 10.5 mm Hg, mean V wave 16.5 mm Hg) and 173 had elevated LAP (mean LAP 19 mm Hg, mean V wave 32.5 mm Hg). The prevalence of severe MR was not different between groups, although the normal LAP group had significantly lower effective regurgitant orifice area and regurgitant volume. Other notable baseline characteristics including prior cardiac surgery, atrial fibrillation, hypertension, diabetes, congestive heart failure, body mass index, mechanism of MR and ejection fraction were similar between groups. However, there was an increased prevalence of chronic lung disease (CLD) (45.2% vs 17.3%, p<0.001) in the normal LAP group. On multivariate analysis, the only significant predictor of normal LAP was the presence of CLD (OR 4.79 (1.83–12.36), p=0.001) and 1-year mortality was significantly higher in the normal LAP group (32.3% vs 12.7%, p=0.006). After adjustment for comorbidities, normal LAP was no longer a predictor of 1-year mortality (RR 1.62 (0.64–4.06), p=0.32); however, CLD (RR 3.44 (1.37–8.67), p=0.01) remained a statistically significant predictor. Conclusion Normal LAP at the time of TMVR is associated with a higher incidence of CLD which independently predicts increased 1-year mortality. In patients with CLD and apparently severe MR, measurement of LAP may help identify those with lower likelihood of benefit from TMVR.

Clinical introduction A man in his 50s presented with abscessed aortic valve methicillin-sensitive Staphylococcus aureus endocarditis, received intravenous antibiotics and underwent bioprosthetic aortic valve replacement with removal of all infected tissues. He returned 18 days later with severe dyspnoea, subjective fever and bilateral lower extremity oedema. Physical examination revealed tachypnoea and tachycardia without fever, prominent neck CV waves visible at 90°, left parasternal heave, 3/6 holosystolic murmur across the precordium, lung rales and severe peripheral oedema. C reactive protein was 211 mg/L (normal <8 mg/L). Blood cultures were obtained. ECG showed sinus tachycardia and right axis deviation. Transthoracic echocardiogram (TTE) parasternal zoomed short-axis systolic frame (figure 1A, B), apical four-chamber systolic frame (figure 1C) and subcostal continuous wave (CW) Doppler (figure 1D), are shown. Question Given the clinical presentation and TTE findings, what is the diagnosis? Severe tricuspid regurgitation due to extension of endocarditis Aortic valve obstruction resulting in severe pulmonary hypertension Acquired Gerbode defect Aortic valve dehiscence with severe paraprosthetic regurgitation