Suri, Rakesh M.

Background Three‐dimensional transthoracic echocardiography (3D‐ TTE ) with dedicated software permits quantification of mitral annulus dynamics and papillary muscle motion throughout the cardiac cycle. Methods and Results Mitral apparatus 3D‐ TTE was acquired in controls (n=42), patients with left ventricle dysfunction and functional mitral regurgitation ( LVD ‐ FMR ; n=43) or without FMR ( LVD ‐no MR , n=35). Annulus in both normal and LVD ‐no MR subjects displayed saddle shape accentuation in early‐systole (ratio of height to intercommissural diameter, 10.6±3.7 to 13.5±4.0 in normal and 9.1±4.3 to 12.6±3.6 in LVD ‐no MR ; P <0.001 for diastole to early‐systole motion, P = NS between those groups). In contrast, saddle shape was unchanged from diastole in FMR patients (10.0±6.4 to 8.0±5.2; P = NS , P <0.05 compared to both other groups). Papillary tips moved symmetrically towards to the midanterior annulus in control and LVD ‐no MR subjects, maintaining constant ratio of the distances between both tips to midannulus (Pt AR ) throughout systole. In LVD ‐ FMR patients midsystolic posterior papillary tip to anterior annulus distance was increased, resulting in higher Pt AR ( P =0.05 compared to both other groups). Mechanisms of early‐ and midsystolic FMR differed between different etiologies of LV dysfunction. In patients with anterior MI and global dysfunction annular function and dilatation were the dominant parameters, while papillary muscle motion was the predominant determinant of FMR in patients with inferior MI . Conclusions Inadequate early‐systolic annular contraction and saddle‐shape accentuation in patients with impaired LV contribute to early–mitral incompetency. Asymmetric papillary tip movement towards the midanterior annulus is a major determinant of mid‐ and late‐systolic functional mitral regurgitation.

Background— Use of the left internal mammary artery (LIMA) in multivessel coronary artery disease improves survival after coronary artery bypass graft surgery; however, the survival benefit of multiple arterial (MultArt) grafts is debated. Methods and Results— We reviewed 8622 Mayo Clinic patients who had isolated primary coronary artery bypass graft surgery for multivessel coronary artery disease from 1993 to 2009. Patients were stratified by number of arterial grafts into the LIMA plus saphenous veins (LIMA/SV) group (n=7435) or the MultArt group (n=1187). Propensity score analysis matched 1153 patients. Operative mortality was 0.8% (n=10) in the MultArt and 2.1% (n=154) in the LIMA/SV ( P =0.005) group, which was not statistically different ( P =0.996) in multivariate analysis or the propensity-matched analysis ( P =0.818). Late survival was greater for MultArt versus LIMA/SV (10- and 15-year survival rates were 84% and 71% versus 61% and 36%, respectively [ P <0.001], in unmatched groups and 83% and 70% versus 80% and 60%, respectively [ P =0.0025], in matched groups). MultArt subgroups with bilateral internal mammary artery/SV (n=589) and bilateral internal mammary artery only (n=271) had improved 15-year survival (86% and 76%; 82% and 75% at 10 and 15 years [ P <0.001]), and patients with bilateral internal mammary artery/radial artery (n=147) and LIMA/radial artery (n=169) had greater 10-year survival (84% and 78%; P <0.001) versus LIMA/SV. In multivariate analysis, MultArt grafts remained a strong independent predictor of survival (hazard ratio, 0.79; 95% confidence interval, 0.66–0.94; P =0.007). Conclusions— In patients undergoing isolated coronary artery bypass graft surgery with LIMA to left anterior descending artery, arterial grafting of the non–left anterior descending vessels conferred a survival advantage at 15 years compared with SV grafting. It is still unproven whether these results apply to higher-risk subgroups of patients.

Background— Few data exist on long-term outcomes of elderly patients after aortic valve replacement. We evaluated latest follow-up information for patients ≥70 years of age after aortic valve replacement. Methods and Results— Late overall survival of 2890 consecutive patients ≥70 years of age who underwent aortic valve replacement between January 1993 and December 2007 was reviewed retrospectively, analyzed, and stratified by preoperative and intraoperative variables. Observed 5-, 10-, and 15-year late postoperative survival was lower than generally expected (68%, 34%, and 8% versus 70%, 42%, and 20%, respectively; P <0.001). Independent predictors of late death included older age, renal failure, diabetes mellitus, stroke, myocardial infarction, immunosuppression, prior coronary artery bypass grafting, implanted pacemaker, lower ejection fraction, hypertension, and New York Heart Association class III or IV. After stratification by age–comorbidity risk score, 10-year survival for the lowest-risk group (n=946 [33%]) was similar to expected survival (55% versus 55%; P =0.50), but for the highest-risk group (n=564 [20%]), survival was significantly lower than expected (9% versus 26%; P <0.001). For 229 pairs of propensity-matched patients with mechanical or biological prostheses, survival was not significantly different (67%, 40%, and 19% versus 71%, 45%, and 7% at 5, 10, and 15 years, respectively; P =0.81). Structural deterioration of bioprostheses occurred in 64 patients (2.4%). Conclusions— Survival of elderly patients after aortic valve replacement is influenced by age and preoperative comorbidities; 33% at lowest risk had overall survival similar to that of an age- and sex-matched general population. There was no sufficient evidence that valve type affected survival. Structural deterioration of aortic bioprostheses was rare.

Background— Left atrium (LA) enlargement is common in organic mitral regurgitation (MR) and is an emerging prognostic indicator. However, outcome implications of LA enlargement have not been analyzed in the context of routine clinical practice and in a multicenter study. Methods and Results— The Mitral Regurgitation International DAtabase (MIDA) registry enrolls patients with organic MR due to flail leaflets, diagnosed in routine clinical practice, in 5 US and European centers. We investigated the relation between LA diameter and mortality under medical treatment and after mitral surgery in 788 patients in sinus rhythm (64±12 years; median LA, 48 [43 to 52] mm). LA diameter was independently associated with survival after diagnosis (hazard ratio, 1.08 [1.04 to 1.12] per 1 mm increment). Compared with patients with LA <55 mm, those with LA ≥55 mm had lower 8-year overall survival ( P <0.001). LA ≥55 mm independently predicted overall mortality (hazard ratio, 3.67 [1.95 to 6.88]) and cardiac mortality (hazard ratio, 3.74 [1.72 to 8.13]) under medical treatment. The association of LA ≥55 mm and mortality was consistent in subgroups. Similar excess mortality associated with LA ≥55 mm was observed in asymptomatic and symptomatic patients ( P for interaction, 0.77). In patients who underwent mitral surgery, LA ≥55 mm had no impact on postoperative outcome ( P >0.20). Mitral surgery was associated with greater survival benefit in patients with LA ≥55 mm compared with LA <55 mm ( P for interaction, 0.008). Conclusions— In MR caused by flail leaflets, LA diameter ≥55 mm is associated with increased mortality under medical treatment, independent of the presence of symptoms or left ventricular dysfunction.

Background— Proposed advantages to the Ross procedure included presumed increased freedom from reoperation and simpler reoperation for pulmonary conduit replacement if needed. It is increasingly apparent, however, that reoperations are frequent after the Ross procedure and that when required, they may be more complex than previously thought. Methods and Results— Between September 1991 and August 2008, 56 patients underwent reoperation at our institution after a Ross procedure performed by ourselves (n=13) or elsewhere (n=43). Median age at first reoperation at our institution was 26 years (range 1 to 69 years). The 4 most common indications for reoperation were isolated autograft (neoaortic) regurgitation in 11 cases (20), isolated pulmonary conduit regurgitation/stenosis in 9 (16), combined autograft regurgitation/dilatation in 8 (14), and combined autograft regurgitation and pulmonary conduit regurgitation/stenosis in 6 (11). A total of 144 procedures were performed in these 56 patients during first reoperation at our institution. The autograft valve required replacement in 21 cases (38) and aortic root replacement in 21 (38), with ascending aortic/arch reconstruction in 13 (23) and mitral valve surgery in 5 (9). The pulmonary valve was replaced in 33 cases (59) and the tricuspid valve was repaired/replaced in 10 (18). Early mortality was 1.8 (1 of 56 patients), and morbidity included 6 patients with respiratory failure and 3 who required postcardiotomy extracorporeal membrane oxygenation. There were 4 late deaths during the median follow-up of 8 months (range 1 to 179 months). Conclusions— A broad spectrum of complex reoperations may be required after the Ross procedure. Patients and family members considering the procedure should be informed of the potential for associated morbidity should reoperation be necessary.

Background— Mitral annulus is a complex structure of poorly understood physiology. Full-volume real-time 3-dimensional transesophageal echocardiography offers a unique opportunity to completely image and quantify mitral annulus size and motion. Methods and Results— Real-time 3-dimensional transesophageal echocardiography of the mitral valve was acquired in 32 patients with myxomatous valve disease (MVD) and moderate to severe regurgitation, 15 normal control subjects, and 10 patients with ischemic mitral regurgitation of identical body surface area. Mitral annular dimensions (circumference, area, anteroposterior and intercommissural diameters, height, and ratio of height to intercommissural diameter ratio, which appraises annular saddle-shape depth) were measured throughout the cardiac cycle with dedicated quantification software. Compared with direct surgical measurement, 3-dimensional anterior annular dimension provided reliable measurements (mean difference, 0.1±0.1 mm; P =0.73; 95% confidence interval, ±4.4 mm). Annular dimensions were larger in MVD patients compared with control subjects in diastole (all P <0.05). Normal annulus displayed early-systolic anteroposterior ( P <0.001) and area ( P =0.04) contraction, increased height ( P <0.001), and deeper saddle shape (ratio of height to intercommissural diameter, 15±1% to 21±1%; P <0.001), whereas intercommissural diameter was unchanged ( P =0.30). In contrast, MVD showed early-systolic intercommissural dilatation ( P =0.02) and no area contraction ( P =0.99), height increase ( P =0.11), or saddle-shape deepening ( P =0.35). Late-systolic MVD annular saddle shape deepened but annular area excessively enlarged ( P <0.04) as a result of persistent intercommissural widening ( P <0.02). MVD annulus also contrasts with ischemic mitral regurgitation annulus, which, despite similar anteroposterior enlargement, is narrower and essentially adynamic. After MVD repair, the annulus remained dynamic without systolic saddle-shape accentuation ( P =0.30). Conclusions— Real-time 3-dimensional transesophageal echocardiography provides insights into normal, dynamic mitral annulus function with early-systolic area contraction and saddle-shape deepening contributing to mitral competency. MVD annulus is also dynamic but considerably different with loss of early-systolic area contraction and saddle-shape deepening despite similar magnitude of ventricular contraction, suggestive of ventricular-annular decoupling. Subsequent area enlargement may contribute to mitral incompetence. After mitral repair, MVD annulus remains dynamic without systolic saddle-shape accentuation. Thus, real-time 3-dimensional transesophageal echocardiography provides new insights that allow the refining of mitral pathophysiology concepts and repair strategies.