Enhanced Recovery After Surgery Is Associated With Reduced Hospital Length of Stay after Urgent or Emergency Isolated Coronary Artery Bypass Surgery at an Urban, Tertiary Care Teaching Hospital: An Interrupted Time Series Analysis With Propensity Score Matching.

OBJECTIVE: To evaluate whether enhanced recovery after surgery (ERAS) was associated with reduced length of stay (LOS) after urgent or emergency coronary artery bypass graft surgery (CABG). DESIGN: A retrospective analysis of an institutional database for urgent or emergency isolated CABG before versus after ERAS. Propensity matching identified comparable subpopulations pre- versus post-ERAS. Interrupted time series analysis was used to evaluate LOS. SETTING: At a tertiary care teaching hospital. PARTICIPANTS: A total of 1,012 patients undergoing urgent or emergent CABG-346 from 2016 to 2017 (pre-ERAS), and 666 from 2018 to 2020 (post-ERAS). Emergent CABG was performed within 24 hours, and urgent CABG was performed during the same hospitalization to reduce clinical risk. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Propensity-matched post-ERAS (n = 565) versus pre-ERAS patients (n = 330) demonstrated reduced LOS (9 [8-13] v (10 [8-14] days p = 0.015), increased likelihood of extubation within 6 hours (46.0% v 35.8%, p = 0.003), shorter ventilation time (6.3 [5.1-10.2] v (7.2 [5.4-12.2] hours, p = 0.003), reduced morphine milligram equivalent use on postoperative days 1 and 2 (69.6 ± 62.2 v 99.0 ± 61.6, p < 0.001), and increased intraoperative ketamine use (58.8% v 35.2%, p < 0.001). There were no differences regarding reintubation, intensive care unit readmission, or 30-day morbidity. Adjusted segmental regression (n = 1,012) for LOS demonstrated reduced mean LOS of approximately 2 days after ERAS (ß2 coefficient -1.943 [-3.766 to -0.121], p = 0.037), with stable trends for mean LOS and no change in slope throughout the pre-ERAS and post-ERAS time periods. CONCLUSIONS: Enhanced recovery after surgery was associated with reduced LOS after urgent or emergency CABG without adverse effects on prolonged ventilation, reintubation, intensive care unit readmission, or 30-day outcomes.

Enhanced Recovery After Surgery Is Associated With Improved Outcomes and Reduced Racial and Ethnic Disparities After Isolated Coronary Artery Bypass Surgery: A Retrospective Analysis With Propensity-Score Matching.

OBJECTIVES: To evaluate whether enhanced recovery after surgery (ERAS) protocol implementation was associated with improved outcomes and decreased racial and ethnic outcome disparities after isolated coronary artery bypass graft (CABG) surgery. DESIGN: A retrospective analysis of an institutional CABG database with propensity-score matching. SETTING: At a single tertiary care teaching hospital. PARTICIPANTS: One thousand seven hundred thirty-five patients undergoing isolated CABG: 656 patients from 2016 to 2017 (pre-ERAS) and 1,079 patients from 2018 to 2020 (post-ERAS). Each patient cohort was divided into a White subgroup and a racial and ethnic minorities (Minorities) subgroup. INTERVENTIONS: None MEASUREMENTS AND MAIN RESULTS: Propensity-matched post-ERAS patients (n = 584) compared to pre-ERAS patients (n = 584) demonstrated reductions in total length of stay (LOS) (median [interquartile range]): (7 [5-10] v 8 [6-11.5] days, p = .006), postoperative LOS (5 [4-7] v 5 [4-7] days, p = .001), total ventilation time (6.1 [4.8-9.5] v 6.6 [5.2-10.9] hours, p = .004), postoperative morphine milligram equivalents (mean ± standard deviation: 68.6 ± 57.5 v 100.0 ± 59.4, p < .001), and increased likelihood of early extubation (48.8% v 42.3%, p = .026); the Minorities subgroup demonstrated reductions in likelihood of intensive care unit (ICU) readmission (1.3% v 8.1%, p = .012) and postoperative morphine milligram equivalents (73.6 ± 64.0 v 107.8 ± 71.9, p < .001). Logistic regression models demonstrated that disparities in ICU readmission and postoperative LOS between White and Minorities patients were eliminated post-ERAS. CONCLUSIONS: ERAS for isolated CABG surgery was associated with reduced total and postoperative LOS, reduced total ventilation time, and increased early extubation for all patients, as well as reduced ICU readmission for the Minorities subgroup. ERAS implementation was associated with reduced disparities between White and racial and ethnic minority patients for ICU readmission and postoperative LOS.

Machine learning models for mitral valve replacement: A comparative analysis with the Society of Thoracic Surgeons risk score.

BACKGROUND: Current Society of Thoracic Surgeons (STS) risk models for predicting outcomes of mitral valve surgery (MVS) assume a linear and cumulative impact of variables. We evaluated postoperative MVS outcomes and designed mortality and morbidity risk calculators to supplement the STS risk score. METHODS: Data from the STS Adult Cardiac Surgery Database for MVS was used from 2008 to 2017. The data included 383,550 procedures and 89 variables. Machine learning (ML) algorithms were employed to train models to predict postoperative outcomes for MVS patients. Each model's discrimination and calibration performance were validated using unseen data against the STS risk score. RESULTS: Comprehensive mortality and morbidity risk assessment scores were derived from a training set of 287,662 observations. The area under the curve (AUC) for mortality ranged from 0.77 to 0.83, leading to a 3% increase in predictive accuracy compared to the STS score. Logistic Regression and eXtreme Gradient Boosting achieved the highest AUC for prolonged ventilation (0.82) and deep sternal wound infection (0.78 and 0.77) respectively. EXtreme Gradient Boosting performed the best with an AUC of 0.815 for renal failure. For permanent stroke prediction all models performed similarly with an AUC around 0.67. The ML models led to improved calibration performance for mortality, prolonged ventilation, and renal failure, especially in cases of reconstruction/repair and replacement surgery. CONCLUSIONS: The proposed risk models complement existing STS models in predicting mortality, prolonged ventilation, and renal failure, allowing healthcare providers to more accurately assess a patient's risk of morbidity and mortality when undergoing MVS.

Relationship of surgeon experience and outcomes of surgery for degenerative mitral valve disease.

OBJECTIVE: To assess the impact of surgeon experience on the outcomes of degenerative mitral valve disease. METHODS: We reviewed all patients who had surgery for degenerative mitral valve disease between 2011 and 2016. Experienced surgeon was defined as performing ≥ 25 mitral valve operations/year. Patient characteristics and outcomes were compared. Competing risk analysis was performed to identify factors associated with mitral regurgitation (MR) recurrence. Survival analysis for mortality was done using Kaplan Meier curve and Cox proportional hazard method. RESULTS: There were 575 patients treated by 9 surgeons for severe MR caused by degenerative mitral valve disease between 2011 and 2016. Three experienced surgeons performed 77.2% of the operations. Patients treated by less experienced surgeons had worse comorbidity profile and were more likely to have an urgent or emergent operation (p = .001). Experienced surgeons were more likely to attempt repair (p = .024), to succeed in repair (94.7% vs. 87%; p = .001), had shorter cross-clamp times (p = .001), and achieved higher repair rate (81.3% vs. 69.7%; p = .005). Experienced surgeons were more likely to use neochordae (p = .001) and less likely to use chordae transfer (p = .001). Surgeon experience was not associated with recurrence of moderate or higher degree of MR after repair but was an independent risk factor for mortality (HR = 2.64; p = .002). CONCLUSIONS: Techniques of degenerative mitral valve surgery differ with surgeon experience, with higher rates of repair and better outcomes associated with more experienced surgeons.

Left main coronary artery occlusion in an asymptomatic patient: late complication after arterial switch operation.

Long-term complications of the arterial switch operation for transposition of the great arteries include coronary artery stenosis and occlusion. We present a patient with high-grade left main coronary artery stenosis 18 years following the arterial switch procedure who was successfully treated with a left internal mammary artery to left anterior descending artery bypass.

Liver laceration from a diaphragmatic suture in minithoracotomy mitral valve repair.

Mitral valve operations are increasingly performed through minimally invasive approaches such as the right anterior minithoracotomy. To facilitate exposure with this technique, a diaphragmatic suture may be implemented. We describe a liver laceration caused by the diaphragmatic suture in minithoracotomy mitral repair and its successful nonoperative management with arterial embolization.

The "free" right internal thoracic artery: a versatile and durable conduit.

BACKGROUND: Despite its potential advantages, the right internal thoracic artery (RITA) is used as a conduit in only 4% of coronary revascularizations. To broaden its application, we frequently use the RITA as a free graft. In this study, we review our experience with the RITA as an in situ and free graft. METHODS: We reviewed the perioperative outcomes and angiographic patency rates of 479 consecutive patients who underwent RITA grafting between January 1987 and December 2011. RESULTS: The RITA was harvested free (FRITA) in 380 patients (79%) and in situ in 99 (21%). The predominant target for the in situ RITA was the right coronary system (79%). The predominant targets for the FRITA were divided between the right (54%) and left coronary systems (46%). There was no perioperative mortality. Mean follow-up was 10 years. Perioperative complications included myocardial infarction (0.4%), sternal nonunions (0.4%), and reoperation for hemorrhage (0.6%). Coronary angiograms were performed in symptomatic patients (17%) after a median of seven years. FRITA patency rates at five, 10, and 15 years were 100%, 95%, and 95%, respectively, comparable to the left internal thoracic artery patency rates and superior to those of saphenous vein graft. Survival rates of FRITA patients at 10, 15, and 20 years were 92%, 89%, and 76%, respectively. CONCLUSION: The FRITA graft reaches all distal coronary vessels and is associated with excellent patency and survival rates. Its application in coronary revascularization vastly expands the benefits of internal thoracic artery grafting.

Impact of Persistent Versus Paroxysmal Preoperative Atrial Fibrillation on In-Hospital, One-Year, and Late Clinical Outcomes Following Transcatheter Aortic Valve Implantation.

Previous reports on the impact of preexisting atrial fibrillation (AF) on clinical outcomes after transcatheter aortic valve implantation (TAVI) have presented limited data on the relative impact of paroxysmal versus persistent AF subtypes. We compared in-hospital, 1-year, and late clinical outcomes in 1,098 patients who underwent TAVI with preoperative AF (556 paroxysmal, 542 persistent) versus 1,787 patients without AF. The propensity-matched cohorts with AF (n = 643) and without AF (n = 686) did not differ with respect to baseline clinical characteristics, operative technique, or in-hospital TAVI complications. At 1-year, patients with AF had higher all-cause mortality (9.0% vs 6.1%, p = 0.046) and readmission rates (13.1 vs 8.8%, p = 0.014), with lower Kansas City cardiomyopathy questionnaire scores (77.8 ± 21.8 vs 84.3 ± 17.1, p <0.001). Echocardiographic follow-up (mean time 455 ± 285 days) demonstrated no significant intergroup differences in hemodynamic findings other than a progressive increase in left atrial volume index in patient subgroups (without AF: 37.4 ± 14.7 ml/m2 vs paroxysmal AF: 46.4 ± 21.4 ml/m2 vs persistent AF: 60.5 ± 26.3 ml/m2, p <0.001). On late follow-up (mean time 49.0 [45.1 to 52.9] months), patients with persistent AF had worse all-cause mortality than patients without AF (hazard ratio 1.55, 95% confidence interval 1.17 to 2.06, p = 0.003), with no significant survival differences between the paroxysmal AF and without AF subgroups. In conclusion, patients with preexisting AF and patients without AF who underwent TAVI had similar in-hospital outcomes but worse 1-year mortality, hospital readmission, and quality of life outcomes. Compared with patients without AF, patients with persistent but not paroxysmal preexisting AF have higher late all-cause mortality at a mean follow-up of 49 months. Patients with persistent AF have higher levels of left atrial volume index than patients with paroxysmal AF and patients without AF on intermediate echocardiographic follow-up.

Half-dose direct oral anticoagulation versus warfarin for atrial fibrillation following cardiac surgery.

BACKGROUND: Optimal anticoagulation strategies have not been defined for patients with atrial fibrillation following cardiac surgery. METHODS: From a total cohort of 228 patients with pre-existing or new onset atrial fibrillation following coronary artery bypass grafting and/or valve surgery, we compared in-hospital and 30-day outcomes in 119 patients treated with low-dose aspirin and a half-dose direct oral anticoagulant (DOAC) versus 109 treated with low-dose aspirin and warfarin. RESULTS: DOAC patients were older (73.1±7.0 vs. 68.7±11.4 years, P<0.001) and had a lower incidence of preoperative atrial fibrillation (37 [31.1%] vs. 69 [63.3%], P<0.001). Otherwise, the two cohorts were well matched for baseline demographics, cardiovascular risk factors, comorbidities, prior cardiac history and STS Risk Score. In comparison to Warfarin patients, DOAC patients had a shorter length of post-surgical stay (6 [5-8] vs. 7 [5-10] days, P=0.037). The two cohorts, however, had a similar incidence of stroke, transient ischemic attack, reoperation for bleeding and postoperative blood bank product usage. Follow-up 30-day outcomes did not differ between the two groups with respect to mortality (0 [0.0%] vs. 0 [0.0%], P=1.000) and hospital readmission (16 [13.4%] vs. 14 [12.8%], P=0.893), although two DOAC patients required drainage of sanguineous pericardial effusions. CONCLUSIONS: In comparison to warfarin, half-dose DOAC anticoagulation in patients with atrial fibrillation following cardiac surgery is associated with a shorter postoperative length of stay, without a significant increase in stroke/transient ischemic attack, reoperation for bleeding or postoperative blood product transfusion. Follow-up echocardiography in anticoagulated patients is recommended to rule out significant sanguineous pericardial effusions in the early postoperative period following hospital discharge.

Modulation of transforming growth factor-ß signaling and extracellular matrix production in myxomatous mitral valves by angiotensin II receptor blockers.

BACKGROUND: Little is known about the pathophysiology of myxomatous degeneration of the mitral valve, the pathological hallmark of mitral valve prolapse, associated with symptomatic mitral regurgitation, heart failure, and death. Excess transforming growth factor (TGF)-ß signaling is known to cause mitral valve degeneration and regurgitation in a mouse model of Marfan syndrome. We examined if TGF-ß signaling is dysregulated in clinical specimens of sporadic mitral valve prolapse compared with explanted nondiseased mitral valves and we tested the effects of angiotensin II receptor blockers on TGF-ß signaling in cultured human mitral valve cells. METHODS AND RESULTS: Operative specimens, cultured valve tissues, and cultured valvular interstitial cells were obtained from patients with mitral valve prolapse undergoing mitral valve repair or from organ donors without mitral valve disease. Increased extracellular matrix in diseased valve tissue correlated with an upregulation of TGF-ß expression and signaling as evidenced by SMAD2/3 phosphorylation. Both TGF-ß ligand and signaling mediators colocalized primarily to valvular interstitial cells suggesting autocrine/paracrine activation. In cultured valve tissue, exogenous TGF-ß increased basal extracellular matrix production, whereas serological neutralization of TGF-ß inhibited disease-driven extracellular matrix overproduction. TGF-ß-induced extracellular matrix production in cultured valvular interstitial cells was dependent on SMAD2/3 and p38 signaling and was inhibited by angiotensin II receptor blockers. CONCLUSIONS: TGF-ß has a profibrotic role in the pathogenesis of sporadic mitral valve prolapse. Attenuation of TGF-ß signaling by angiotensin II receptor blockers may represent a mechanistically based strategy to modulate the pathological progression of mitral valve prolapse in patients.

Intermediate Follow-Up of Balloon-Expandable Versus Self-Expanding Transcatheter Aortic Valve Implantation in Patients With Small Aortic Annuli.

The clinical impact of prosthesis-patient mismatch (PPM) in patients with small aortic annuli who underwent transcatheter aortic valve (AV) implantation with either balloon-expandable (BE) or self-expanding (SE) valves remains controversial. We assessed in-hospital and intermediate clinical outcomes in 573 patients with transfemoral transcatheter AV implantation with a small AV annulus, defined as an AV annulus area ≤430 mm2. A total of 337 patients treated with a 23-mm BE valve (SAPIEN 3, Ultra) were compared with 236 patients treated with a 26-mm SE valve (Evolut series). Valve-in-valve cases were excluded, and late echo follow-up (mean 674 ± 438 days) was assessed in a subset of 292 patients (51.0%). Well-matched BE and SE cohorts did not differ with respect to major in-hospital outcomes, other than a borderline increase in vascular complications and composite bleeding in patients with SE. Patients with BE had a higher incidence of severe PPM on discharge echocardiography (16.9% vs 6.8%, p <0.002). The mean AV gradient at 30 days was higher for patients with BE (12.2 ± 4.2 vs 6.2 ± 7.9 mm Hg, p <0.001) and at late follow-up (14.0 ± 8.2 vs 7.2 ± 3.5 mm Hg, p <0.001). The follow-up left ventricular ejection fraction and incidence of >mild aortic insufficiency were similar. All-cause mortality for the 2 cohorts was similar, with an overall mean (95% confidence interval) survival time of 61.2 months (57.8 to 64.5; p = 0.98). There were no significant survival differences between combined patients with BE and SE with no, moderate, or severe PPM, with an overall mean (95% confidence interval) survival time of 32.5 (30.5 to 34.5) months combining valve types (p = 0.23). In conclusion, despite an increased incidence of PPM with higher mean AV gradients that persist on late echocardiography in the BE cohort, patients with BE and SE with small aortic annuli have similar clinical outcomes at intermediate follow-up. Moderate and severe PPM had no impact on survival at a mean follow-up of 32.5 months.

Impact of Ticagrelor Versus Clopidogrel on Bleeding Outcomes of Isolated Coronary Artery Bypass Grafting.

BACKGROUND: Increased bleeding risks have been documented in patients exposed to P2Y12 inhibitors within 5 days of coronary artery bypass surgery (CABG). This study aimed to determine the relative CABG bleeding risks of clopidogrel versus ticagrelor exposure and the proper time course of ticagrelor discontinuation prior to surgery. METHODS: Clinical outcomes were assessed in 2075 isolated CABG patients, including 375 who had received P2Y12 inhibitors within 5 days of surgery (155 clopidogrel, 213 ticagrelor, 7 prasugrel). BARC-4 CABG bleeding complications and perioperative blood product usage were assessed in propensity-matched P2Y12-inhibited and non-P2Y12-inhibited cohorts. RESULTS: P2Y12-inhibited patients (n = 375) in comparison to matched non-P2Y12-inhibited patients (n = 1138) had higher rates of re-operation for bleeding (3.8 % vs 1.3 %, p = 0.003), postoperative red blood cell transfusion ≥5 units (5.7 % vs 2.7 %, p = 0.007), and intraoperative and postoperative blood product utilization (42.3 % vs 27.1 %, p < 0.001; 41.8 % vs 32.2 %, p < 0.001, respectively). Univariate predictors of BARC-4 bleeding included clopidogrel (OR: 2.145, 95 % CI: 1.131-4.067, p = 0.019) and ticagrelor discontinued within 3 days of surgery (OR: 2.153, 95 % CI: 1.003-4.169, p = 0.049). Multivariate logistic regression demonstrated that only clopidogrel exposure was an independent BARC-4 bleeding predictor (OR: 1.850, 95 % CI: 1.007-3.398, p = 0.048). Unadjusted ticagrelor patients with drug discontinuation 4-5 days prior to CABG only demonstrated higher rates of perioperative platelet transfusion, without additional signs of excessive bleeding. CONCLUSIONS: Clopidogrel exposure within 5 days of CABG is an independent predictor of BARC-4 bleeding, whereas major ticagrelor bleeding effects are confined to drug exposure within 3 days of surgery.

Racial and ethnic disparities in the treatment and outcomes for witnessed out-of-hospital cardiac arrest in Connecticut.

BACKGROUND: Racial and ethnic disparities in the treatment and outcomes for witnessed out-of-hospital cardiac arrest (OHCA) in the United States have been previously described. We sought to characterize disparities in pre-hospital care, overall survival, and survival with favorable neurological outcomes following witnessed OHCA in the state of Connecticut. METHODS: We performed a cross-sectional study to compare pre-hospital treatment and outcomes for White versus Black and Hispanic (Minority) OHCA patients submitted from Connecticut to the Cardiac Arrest Registry to Enhance Survival (CARES) between 2013 and 2021. Primary outcomes included bystander CPR use, bystander automated external defibrillator (AED) use with attempted defibrillation, overall survival, and survival with favorable cerebral function. RESULTS: 2,809 patients with witnessed OHCA were analyzed (924 Black or Hispanic; 1885 White). Minorities had lower rates of bystander CPR (31.4% vs 39.1%, P = 0.002) and bystander AED placement with attempted defibrillation (10.5% vs 14.4%, P = 0.004), with lower rates of survival to hospital discharge (10.3% vs 14.8%, P = 0.001) and survival with favorable cerebral function (65.3% vs 80.2%, P = 0.003). Minorities were less likely to receive bystander CPR in communities with median annual household income >$80, 000 (OR, 0.56; 95% CI, 0.33-0.95; P = 0.030) and in integrated neighborhoods (OR, 0.70; 95% CI, 0.52-0.95; P = 0.020). CONCLUSIONS: Black and Hispanic Connecticut patients with witnessed OHCA have lower rates of bystander CPR, attempted AED defibrillation, overall survival, and survival with favorable neurological outcomes compared to White patients. Minorities were less likely to receive bystander CPR in affluent and integrated communities.

Propensity-matched comparison of right mini-thoracotomy versus median sternotomy for isolated mitral valve repair.

BACKGROUND: A right mini-thoracotomy (RT) versus median sternotomy (MS) approach for isolated mitral valve (MV) repair has been associated with less postoperative morbidity, shorter hospital stay, and faster functional recovery, but with consistently longer cross-clamp time and higher operative costs. METHODS: We assessed the impact of a modified operative technique on outcomes in 158 RT versus 129 MS patients treated with myxomatous MV repair from 2016 through 2021. Propensity matching based upon the Society of Thoracic Surgeons Risk Score was used to compare 108 patients in each cohort. RESULTS: Propensity-matched RT patients had reductions in total ventilation time (P=0.025), postoperative atrial fibrillation (P=0.019), and hospital length of stay (P<0.001). RT and MS patients had similar cross-clamp times (66.4±13.7 vs 64.8±16.0 minutes, P=0.414), with less overall leaflet resection (32.4% vs 57.4%, P<0.001) and fewer Gore-Tex NeoChords implanted per patient (1.7±0.7 vs 2.1±1.0, P=0.028) in the RT group. The two cohorts did not differ with respect to 30-day major surgical complications. No patient died and there was no difference between the two groups with respect to freedom from re-operation (98.2% vs 98.2%, P=0.800) at a mean follow-up of 21.4±18.5 months. Direct total hospital costs were lower for the RT group (P=0.018), with reductions in postoperative charges offsetting increased operating room costs. CONCLUSIONS: In this single-center study, the RT compared to the MS approach for myxomatous MV repair resulted in less postoperative morbidity and shorter hospital length of stay, with similar cross-clamp time, reduced total hospital costs, and comparable intermediate outcomes.

Author Correction: New insights into mitral heart valve prolapse after chordae rupture through fluid-structure interaction computational modeling.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Atrial fibrillation and mitral valve repair.

Atrial fibrillation (AF) is present in 30-40% of patients presenting for mitral valve surgery. In patients undergoing mitral valve repair, the presence of AF may be associated with increased mortality and morbidity and this is also the case in patients in whom AF persists postoperatively. Advances in understanding the pathogenesis of AF led to techniques that include both mitral valve repair and ablation of AF. The concomitant surgical treatment of AF during mitral surgery has become a commonly performed procedure, which was shown to be safe and which may improve the outcome for patients. AF after mitral valve replacement is an accepted indication for anticoagulation, but the data supporting anticoagulation in patients after mitral valverepair who convert to sinus rhythm are sparse. This article reviews the available data regarding outcomes of mitral repair and how they are influenced by AF and its therapy.

Solving the puzzle of chronic ischemic mitral regurgitation.

Chronic ischemic mitral regurgitation is a prevalent problem among patients following a myocardial infarction. Until recently, the pathophysiology was poorly understood, resulting in surgical strategies with suboptimal results and limited durability. The surgical approach has evolved from revascularization alone to an additional mitral valve procedure, replacement, or repair. When the valve was repaired, isolated annuloplasty was performed. The dilemma that surgeons had when repairing a mitral valve was which type of ring to use and what size. In all series with annuloplasty alone, the results were poor with very high recurrence rates. The primary feature of ischemic mitral regurgitation is a prolapse of the anterior leaflet at A3 +/- A2. This prolapse can be caused by fibrotic elongation of the papillary muscle supporting A3 +/- A2 or tethering of P3 by a ballooning posterior left ventricular wall. Using a technique that corrects this prolapse with Gore-Tex neochords, we have achieved excellent results with effective and durable correction of the ischemic mitral regurgitation.

New insights into mitral heart valve prolapse after chordae rupture through fluid-structure interaction computational modeling.

Mitral valve (MV) dynamics depends on a force balance across the mitral leaflets, the chordae tendineae, the mitral annulus, the papillary muscles and the adjacent ventricular wall. Chordae rupture disrupts the link between the MV and the left ventricle (LV), causing mitral regurgitation (MR), the most common valvular disease. In this study, a fluid-structure interaction (FSI) modeling framework is implemented to investigate the impact of chordae rupture on the left heart (LH) dynamics and severity of MR. A control and seven chordae rupture LH models were developed to simulate a pathological process in which minimal chordae rupture precedes more extensive chordae rupture. Different non-eccentric and eccentric regurgitant jets were identified during systole. Cardiac efficiency was evaluated by the ratio of external stroke work. MV structural results showed that basal/strut chordae were the major load-bearing chordae. An increased number of ruptured chordae resulted in reduced basal/strut tension, but increased marginal/intermediate load. Chordae rupture in a specific scallop did not necessarily involve an increase in the stress of the entire prolapsed leaflet. This work represents a further step towards patient-specific modeling of pathological LH dynamics, and has the potential to improve our understanding of the biomechanical mechanisms and treatment of primary MR.

Finite Element Analysis of Tricuspid Valve Deformation from Multi-slice Computed Tomography Images.

Despite the growing clinical interest in the tricuspid valve (TV), there is an incomplete understanding of TV biomechanics which is important in normal TV function and successful TV repair techniques. Computational models with patient-specific human TV geometries can provide a quantitative understanding of TV biomechanic. Therefore, this study aimed to develop finite element (FE) models of human TVs from multi-slice computed tomography (MSCT) images to investigate chordal forces and leaflet stresses and strains. Three FE models were constructed for human subjects with healthy TVs from MSCT images and incorporated detailed leaflet geometries, realistic nonlinear anisotropic hyperelastic material properties of human TV, and physiological boundary conditions tracked from MSCT images. TV closure from diastole to systole was simulated. Chordal lengths were iteratively adjusted until the simulated TV geometries were in good agreement with the "true" geometries reconstructed from MSCT images at systole. Larger chordal forces were found on the strut (or basal) chords than on the rough zone chords and the total forces applied on the anterior papillary muscles by the strut chords were higher than those on the posterior or septal papillary muscles. At peak systolic pressure, the average maximum stress on the middle sections of the leaflets ranged from 30 to 90 kPa, while the average maximum principal strain values ranged from 0.16 to 0.30. The results from healthy TVs can serve as baseline biomechanical metrics of TV mechanics and may be used to inform TV repair device design. The computational approach developed could be one step towards developing computational models that may support pre-operative planning in complex TV repair procedures in the future.