Intraoperative assessment of mitral valve repair: Validation of the saline test with nonresectional repair techniques.

BACKGROUND AND AIM: Intraoperative assessment of the repaired mitral valve (MV) by saline testing is a standard maneuver in MV repair. Despite a growing interest in application of nonresectional techniques, the utility of the saline test following repair with neochordae has not been systematically assessed. We sought to determine the accuracy of the saline test following MV repair using nonresectional techniques. MATERIALS AND METHODS: We included 25 adult patients undergoing MV repair for degenerative valve disease between November 2018 and February 2019. The surgical repair was performed using nonresectional techniques with neochordae either through a sternotomy or a robotic approach. RESULTS: Twenty-five patients underwent successful MV repair, all with excellent echocardiographic results. In four patients (16%), the saline test suggested discrete areas of leaflet malcoaptation and leakage, leading to additional repair maneuvers. In 16 patients (64%), the final saline test demonstrated excellent coaptation with little or no leak. In nine patients (36%), the final saline test was inconclusive (ventricle could not be filled) or poor (diffuse leak). Post-repair intraoperative echocardiography demonstrated no or trivial mitral regurgitation in all patients, and no patient required a second pump run. CONCLUSION: After repair with neochordae, a satisfactory saline test indicates a good repair and discrete leaks on the saline test suggest the need for further surgical maneuvers. If the surgeon has employed standard repair techniques using neochordae but the saline test is inconclusive or poor, additional repair maneuvers are generally unnecessary, as intraoperative echocardiography will usually demonstrate a good repair.

Assessment of Mitral Valve Repair With Exercise Echocardiography: Artificial Chordae vs Leaflet Resection.

Mitral valve (MV) repair with artificial chordae (AC) or leaflet resection (LR) is associated with good hemodynamics at rest. The aim of this study was to compare these techniques in terms of exercise capacity and echocardiographic parameters of hemodynamics at rest and peak exercise. We conducted a study in 2015 of 56 patients, who had undergone surgery for degenerative posterior mitral leaflet prolapse between 2005 and 2014 using either AC (n = 24) or LR (n = 32). Clinical data were collected, exercise capacity was measured, and resting echocardiography and peak exercise echocardiography were performed. No significant differences were detected among groups regarding exercise duration or peak exercise workload measured in Watts (W) (AC: 136 ± 43 W and LR: 131 ± 40 W; P = 0.65). The mean mitral gradient at rest was 3.0 ± 1.3 mm Hg in the AC group and 3.0 ± 1.0 mm Hg in the LR group (P = 0.90). The mean MV gradients at peak exercise did not differ significantly between groups (AC: 8.3 ± 3.4 and LR: 11.3 ± 8.7; P = 0.19). Four patients (17%) in the AC group and 1 (3%) in the LR group had systolic anterior motion, P = 0.15. We conclude that both methods of posterior MV leaflet repair were associated with good hemodynamics at rest and peak exercise. The groups had comparable exercise capacity. MV pressure gradients at rest and peak exercise were similar in both groups.

Three-dimensional assessment of papillary muscle displacement in a porcine model of ischemic mitral regurgitation.

OBJECTIVE: Papillary muscle displacement relative to mitral annulus is pivotal in chronic functional ischemic mitral regurgitation. Analysis of 3-dimensional papillary muscle displacement has relied on invasive measurement. In this study, we used noninvasive clinically applicable 3-dimensional morphology cardiac magnetic resonance imaging to define papillary muscle position in a 3-dimensional matrix. METHODS: Fifty pigs (approximately 50 kg) were subjected to posterolateral myocardial infarction and tachycardiac stress. Fourteen animals survived 6 weeks: 10 acquired chronic functional ischemic mitral regurgitation at least grade II and 4 did not. Animals were examined by 3-dimensional morphology cardiac magnetic resonance imaging, and dedicated software enabled assessment of anterior and posterior papillary muscle positions relative to anterior and posterior trigones and posterior mitral annulus. Animals with functional ischemic mitral regurgitation were compared with those without and with 10 healthy controls. RESULTS: Relative to controls, animals with functional ischemic mitral regurgitation at end systole had significantly higher displacements of the posterior papillary muscle from anterior and posterior trigones in lateral and posterior directions, and of anterior papillary muscle from anterior and posterior trigones in apical direction. Relative to animals without functional ischemic mitral regurgitation, there was significantly higher posterior papillary muscle displacement from posterior trigone in lateral direction. Interpapillary muscle distance was the strongest predictor of regurgitant volume (r(2) = 0.85, P < .001). CONCLUSIONS: Three-dimensional morphology cardiac magnetic resonance imaging enabled detailed analysis of local left ventricular remodeling effects causing functional ischemic mitral regurgitation.

Health care consumption due to atrial fibrillation is markedly reduced by Maze III surgery.

BACKGROUND: Health care consumption and costs for the treatment of atrial fibrillation are high. Atrial fibrillation is effectively treated by the surgical Maze III procedure according to the Cox method. We describe the effects of this procedure on health care consumption and economy. METHODS: From October 1997 through March 2002, 72 patients underwent the Maze III procedure. Medical records of these patients were reviewed, and all data regarding hospitalization and outpatient clinic visits for atrial fibrillation and its related diseases were recorded. Accounting divisions from the contributing hospitals were consulted for the exact cost of each of these services, which were allocated into preoperative, perioperative, and postoperative periods. RESULTS: The perioperative mortality was zero. Long-term freedom from symptomatic atrial fibrillation was verified in 96% of the patients. The number of hospitalization days decreased by 84%, from 471 during the preoperative period to 79 in the postoperative (p < 0.001), and costs during the same periods decreased by 75%, from 7,075,000 Swedish Kronor to 1,757,000 Swedish Kronor (p < 0.001). CONCLUSIONS: The Maze III procedure significantly decreased the postoperative hospitalization costs in patients undergoing surgery primarily for atrial fibrillation. As well as providing an effective treatment for symptomatic arrhythmia, this procedure breaks the undesirable trend of increasing health care consumption resulting from treatment of atrial fibrillation.

Transplantation of lungs from non-heart-beating donors after functional assessment ex vivo.

BACKGROUND: If lungs from patients dying of heart attacks are to serve as donor organs in a safe way, their function should be properly assessed before transplantation. The aim of this study was to investigate donor lung function evaluation in a realistic large animal model. METHODS: Twelve 60-kg pigs were used. Five minutes after ventricular fibrillation was induced, cardiopulmonary resuscitation was initiated and maintained for 20 minutes. After a 10-min hands-off period, heparin was administered through a central venous catheter followed by 20 chest compressions. Intrapleural cooling was initiated after 65 minutes of warm ischemia. Cooling proceeded for 6 hours within the cadaver, after which lung function was assessed ex vivo. Recipient pigs underwent left lung transplantation followed by right pneumonectomy, thus making these animals 100% dependent for their survival on the function of the donor lungs. RESULTS: The assessment showed that all lungs had adequate function to serve as donor lungs. All recipient animals were in good condition during the 24-hour observation period after the operation. The blood gas function did not differ significantly from that in the healthy donor animals before induction of ventricular fibrillation; pulmonary vascular resistance was within normal range. CONCLUSIONS: Lungs from non-heart-beating donors topically cooled in situ for 6 hours after 65 minutes of warm ischemia were assessed ex vivo and found to have normal function. They were then transplanted and retained normal function during a 24-hour observation period.