Current Therapeutic Options in Aortic Stenosis.

Aortic stenosis is the most common valvular disease requiring valve replacement. Valve replacement therapies have undergone progressive evolution since the 1960s. Over the last 20 years, transcatheter aortic valve replacement has radically transformed the care of aortic stenosis, such that it is now the treatment of choice for many, particularly elderly, patients. This review provides an overview of the pathophysiology, presentation, diagnosis, indications for intervention, and current therapeutic options for aortic stenosis.

Procedural Volume and Outcomes for Transcatheter Aortic-Valve Replacement.

BACKGROUND: During the introduction of transcatheter aortic-valve replacement (TAVR) in the United States, requirements regarding procedural volume were mandated by the Centers for Medicare and Medicaid Services as a condition of reimbursement. A better understanding of the relationship between hospital volume of TAVR procedures and patient outcomes could inform policy decisions. METHODS: We analyzed data from the Transcatheter Valve Therapy Registry regarding procedural volumes and outcomes from 2015 through 2017. The primary analyses examined the association between hospital procedural volume as a continuous variable and risk-adjusted mortality at 30 days after transfemoral TAVR. Secondary analysis included risk-adjusted mortality according to quartile of hospital procedural volume. A sensitivity analysis was performed after exclusion of the first 12 months of transfemoral TAVR procedures at each hospital. RESULTS: Of 113,662 TAVR procedures performed at 555 hospitals by 2960 operators, 96,256 (84.7%) involved a transfemoral approach. There was a significant inverse association between annualized volume of transfemoral TAVR procedures and mortality. Adjusted 30-day mortality was higher and more variable at hospitals in the lowest-volume quartile (3.19%; 95% confidence interval [CI], 2.78 to 3.67) than at hospitals in the highest-volume quartile (2.66%; 95% CI, 2.48 to 2.85) (odds ratio, 1.21; P = 0.02). The difference in adjusted mortality between a mean annualized volume of 27 procedures in the lowest-volume quartile and 143 procedures in the highest-volume quartile was a relative reduction of 19.45% (95% CI, 8.63 to 30.26). After the exclusion of the first 12 months of TAVR procedures at each hospital, 30-day mortality remained higher in the lowest-volume quartile than in the highest-volume quartile (3.10% vs. 2.61%; odds ratio, 1.19; 95% CI, 1.01 to 1.40). CONCLUSIONS: An inverse volume-mortality association was observed for transfemoral TAVR procedures from 2015 through 2017. Mortality at 30 days was higher and more variable at hospitals with a low procedural volume than at hospitals with a high procedural volume. (Funded by the American College of Cardiology Foundation National Cardiovascular Data Registry and the Society of Thoracic Surgeons.).

Transcatheter Aortic-Valve Replacement with a Self-Expanding Valve in Low-Risk Patients.

BACKGROUND: Transcatheter aortic-valve replacement (TAVR) is an alternative to surgery in patients with severe aortic stenosis who are at increased risk for death from surgery; less is known about TAVR in low-risk patients. METHODS: We performed a randomized noninferiority trial in which TAVR with a self-expanding supraannular bioprosthesis was compared with surgical aortic-valve replacement in patients who had severe aortic stenosis and were at low surgical risk. When 850 patients had reached 12-month follow-up, we analyzed data regarding the primary end point, a composite of death or disabling stroke at 24 months, using Bayesian methods. RESULTS: Of the 1468 patients who underwent randomization, an attempted TAVR or surgical procedure was performed in 1403. The patients' mean age was 74 years. The 24-month estimated incidence of the primary end point was 5.3% in the TAVR group and 6.7% in the surgery group (difference, -1.4 percentage points; 95% Bayesian credible interval for difference, -4.9 to 2.1; posterior probability of noninferiority >0.999). At 30 days, patients who had undergone TAVR, as compared with surgery, had a lower incidence of disabling stroke (0.5% vs. 1.7%), bleeding complications (2.4% vs. 7.5%), acute kidney injury (0.9% vs. 2.8%), and atrial fibrillation (7.7% vs. 35.4%) and a higher incidence of moderate or severe aortic regurgitation (3.5% vs. 0.5%) and pacemaker implantation (17.4% vs. 6.1%). At 12 months, patients in the TAVR group had lower aortic-valve gradients than those in the surgery group (8.6 mm Hg vs. 11.2 mm Hg) and larger effective orifice areas (2.3 cm2 vs. 2.0 cm2). CONCLUSIONS: In patients with severe aortic stenosis who were at low surgical risk, TAVR with a self-expanding supraannular bioprosthesis was noninferior to surgery with respect to the composite end point of death or disabling stroke at 24 months. (Funded by Medtronic; ClinicalTrials.gov number, NCT02701283.).

Five-year results of the STABLE II study for the endovascular treatment of complicated, acute type B aortic dissection with a composite device design.

OBJECTIVE: To provide the 5-year outcomes of the use of a composite device (proximal covered stent graft + distal bare stent) for endovascular repair of patients with acute, type B aortic dissection complicated by aortic rupture and/or malperfusion. METHODS: Study of Thoracic Aortic Type B Dissection Using Endoluminal Repair (STABLE) II was a prospective, multicenter study of the Zenith Dissection Endovascular System (William Cook Europe). Patients were enrolled between August 2012 and January 2015 at sites in the United States and Japan. Five-year follow-up was completed by January 2020. RESULTS: In total, 73 patients (mean age: 60.7 ± 10.9 years; 65.8% male) with acute type B dissection complicated by malperfusion (72.6%), rupture (21.9%), or both (5.5%) were enrolled. Patients were treated with either a composite device (79.5%) or the proximal stent graft alone (no distal bare stent, 20.5%). Dissections were more extensive in patients who received the composite device (408.9 ± 121.3 mm) than in patients who did not receive a bare stent (315.9 ± 100.1 mm). The mean follow-up was 1209.4 ± 754.6 days. Freedom from all-cause mortality was 80.3% ± 4.7% at 1 year and 68.9% ± 7.3% at 5 years. Freedom from dissection-related mortality remained at 97.1% ± 2.1% from 1-year through 5-year follow-up. Within the stent-graft region, the rate of either complete thrombosis or elimination of the false lumen increased over time (82.1% of all patients at 5 years vs 55.7% at first postprocedure computed tomography), with a higher rate at 5 years in patients who received the composite device (90.5%) compared with patients without the bare stent (57.1%). Throughout the follow-up, overall true lumen diameter increased within the stent-graft region, and overall false lumen diameter decreased. At 5 years, 20.7% of patients experienced a decrease in maximum transaortic diameter within the stent-graft region, 17.2% experienced an increase, and 62.1% experienced no change. Distal to the treated segment (but within the dissected aorta), 23.1% of patients experience no change in transaortic diameter at 5 years; a bare stent was deployed in all these patients at the procedure. Five-year freedom from all secondary intervention was 70.7% ± 7.2%. CONCLUSIONS: These 5-year outcomes indicate a low rate of dissection-related mortality for the Zenith Dissection Endovascular System in the treatment of patients with acute, complicated type B aortic dissection. Further, these data suggest a positive influence of composite device use on false lumen thrombosis. Continuous monitoring for distal aortic growth is necessary in all patients.

Midterm Outcomes of Isolated Coronary Artery Bypass Grafting in the Setting of Moderate Ischemic Mitral Regurgitation.

INTRODUCTION: Although randomized trial data exist for 2-y outcomes comparing isolated coronary artery bypass grafting (CABG) versus CABG with concomitant mitral valve repair (CABG + MVr) for the treatment of moderate ischemic mitral regurgitation (IMR), longer term outcomes are unclear. This study evaluated the longitudinal outcomes of isolated CABG for moderate IMR. METHODS: Patients with moderate IMR undergoing isolated CABG from January 2010 to February 2018 at a single institution were included. Outcomes included longitudinal freedom from heart failure readmission, survival, rates of persistent mitral regurgitation (MR), and freedom from mitral valve reinterventions. A subanalysis was conducted comparing CABG versus CABG + MVr. Multivariable Cox regression was used for risk adjustment. RESULTS: A total of 528 patients with moderate IMR underwent isolated CABG. Postoperatively, 26% of patients had at least moderate MR at 1-mo follow-up, although at 5 y progression to severe MR was rare (2.2%) as were mitral valve reinterventions (0.2%). Survival at 30 d (95.8%), 1 y (89.6%), and 5 y (76.6%) was acceptable. Furthermore, the freedom from readmission for heart failure was also acceptable at 30 d (92.6%), 1 y (79.9%), and 5 y (65.0%) postoperatively. In a subanalysis comparing CABG versus CABG + MVr, unadjusted and risk-adjusted survival, freedom from heart failure readmissions, mitral valve reinterventions, and degrees of MR were comparable between the groups at all intervals (all P > 0.05). CONCLUSIONS: The majority of patients with moderate IMR can undergo isolated CABG with acceptable rates of heart failure readmissions, survival, progression to severe MR, and the need for subsequent mitral interventions. These data support the use of isolated CABG in patients with moderate IMR.

Fate of the Kidneys in Patients with Post-Operative Renal Failure After Cardiac Surgery.

BACKGROUND: This study evaluates the clinical and renal-related outcomes in patients with acute renal failure (ARF) following cardiac surgery. METHODS: Index adult cardiac operations at a single institution from 2010-2018 were reviewed. Patients requiring dialysis pre-operatively were excluded. ARF was stratified as either creatinine rise (≥3-times baseline or ≥4.0 mg/dL) or post-operative dialysis. Outcomes included mortality, rates of progression to dialysis, and renal recovery. Multivariable Cox regression was used for risk-adjustment. RESULTS: A total of 10,037 patients, including 6,275 (62.5%) isolated coronary artery bypass grafting (CABG), 2,243 (22.3%) isolated valve, and 1,519 (15.1%) CABG plus valve cases, were included. Post-operative ARF occurred in 346 (3.5%) patients, with 230 (66.5%) requiring dialysis. Survival was significantly reduced in patients with ARF at 30-days (97.9 versus 70.8%, P <0.001), 1-year (94.9 versus 48.0%, P <0.001), and 5-years (86.2 versus 38.2%, P <0.001) with more profound reductions in those requiring dialysis, findings which persisted after risk-adjustment. Progression to subsequent dialysis in the creatinine rise group was rare (n = 1). The median time to dialysis initiation in the dialysis group was 5 days (IQR 2-12 days) with a median time of dialysis dependence of 72 days (IQR 38-1229 days). Of those patients requiring postoperative dialysis, 30.9% demonstrated renal recovery. CONCLUSIONS: Post-operative ARF and in particular the need for dialysis are associated with substantial reductions in survival that persist during longitudinal follow-up. This occurs despite the finding that patients experiencing creatinine rise only rarely progress to dialysis, and that nearly one-third of patients requiring post-operative dialysis recover renal function.

Concomitant tricuspid valve surgery is beneficial at the time of left-sided valve surgery.

BACKGROUND: This study evaluates the impact of secondary functional tricuspid regurgitation (TR) and concomitant tricuspid valve repair (TVr) at the time of left-sided valve operations. METHODS: Adults undergoing left-sided valve operations between 2010 and 2019 at a multihospital academic institution were included. Patients were stratified into three groups: less-than-moderate TR without TVr (Group 1), moderate-or-greater TR without TVr (Group 2), and moderate-or-greater TR with TVr (Group 3). Primary outcomes included survival and hospital readmissions. Secondary outcomes included major postoperative morbidities. Multivariable logistic regression evaluated risk-adjusted mortality and readmission. RESULTS: About 3444 patients were included in the analysis and were stratified into Group 1 (n = 2612, 75.8%), Group 2 (n = 563, 16.3%), and Group 3 (n = 269, 7.8%). Patients with moderate or greater TR (Groups 2 and 3) had higher rates of mortality, hospital readmissions and major postoperative complications including reoperations, renal failure requiring dialysis, blood transfusions, and prolonged ventilation (all, p < .05). When assessed individually, the Group 3 had substantially higher rates of renal failure requiring dialysis, prolonged ventilation, and reoperations, although the Group 2 had higher rates of 30-day mortality (all, p < .05). These findings persisted in risk-adjusted analysis with the highest hazards for mortality (hazard ratio [HR] 1.9, 95% confidence interval [CI] 1.7-2.2) and readmission (HR 1.3, 95% CI 1.2-1.5) appreciated in the Group 2. CONCLUSIONS: In this analysis of 3444 patients, those with moderate-to-severe TR who did not undergo a TVr at the time of their left-sided valve operation had substantially higher risks of mortality and hospital readmissions compared with those who did undergo TV surgery.

STratification risk analysis in OPerative management (STOP score) for drug-induced endocarditis.

BACKGROUND: The opioid epidemic has seen a drastic increase in the incidence of drug-associated infective endocarditis (IE). No clinical tool exists to predict operative morbidity and mortality in patients undergoing surgery. METHODS: A multi-institutional database was reviewed between 2011 and 2018. Multivariate logistic regression was fitted in an automated stepwise fashion. The STratification risk analysis in OPerative management of drug-associated IE (STOP) score was constructed. Morbidity was defined as reintubation, prolonged ventilation, pneumonia, renal failure, dialysis, stroke, reoperation for bleeding, and a permanent pacemaker. Cross-validation provided an unbiased estimate of out-of-sample performance. RESULTS: A total of 1181 patients underwent surgery for drug-associated IE (median age, 39; interquartile range [IQR], 30-54, 386 women [32.7%], 341 reoperations for prosthetic valve endocarditis [28.9%], 316 patients with multivalve disease [26.8%]). Operative morbidity and mortality were 41.1% and 5.9%, respectively. Predictors of morbidity were dialysis (95% confidence interval [CI], 1.16-2.82), emergent intervention (1.83-4.73), multivalve procedure (1.01-1.98), causative organisms other than Streptococcus (1.09-2.02), and type of valve procedure performed [aortic valve procedure (1.07-2.15), mitral valve replacement (1.03-2.05), tricuspid valve replacement (1.21-2.60)]. Predictors of mortality were dialysis (1.29-5.74), active endocarditis (1.32-83), lung disease (1.25-5.43), emergent intervention (1.69-6.60), prosthetic valve endocarditis (1.24-3.69), aortic valve procedure (1.49-5.92) and multivalve disease (1.00-2.95). Variables maximizing explanatory power were translated into a scoring system. Each point increased odds of morbidity and mortality by 22.0% and 22.4% with an accuracy of 94.0% and 94.1%, respectively. CONCLUSION: Drug-related IE is associated with significant morbidity and mortality. An easily-applied risk stratification score may aid in clinical decision-making.

Surgical or Transcatheter Aortic-Valve Replacement in Intermediate-Risk Patients.

BACKGROUND: Although transcatheter aortic-valve replacement (TAVR) is an accepted alternative to surgery in patients with severe aortic stenosis who are at high surgical risk, less is known about comparative outcomes among patients with aortic stenosis who are at intermediate surgical risk. METHODS: We evaluated the clinical outcomes in intermediate-risk patients with severe, symptomatic aortic stenosis in a randomized trial comparing TAVR (performed with the use of a self-expanding prosthesis) with surgical aortic-valve replacement. The primary end point was a composite of death from any cause or disabling stroke at 24 months in patients undergoing attempted aortic-valve replacement. We used Bayesian analytical methods (with a margin of 0.07) to evaluate the noninferiority of TAVR as compared with surgical valve replacement. RESULTS: A total of 1746 patients underwent randomization at 87 centers. Of these patients, 1660 underwent an attempted TAVR or surgical procedure. The mean (±SD) age of the patients was 79.8±6.2 years, and all were at intermediate risk for surgery (Society of Thoracic Surgeons Predicted Risk of Mortality, 4.5±1.6%). At 24 months, the estimated incidence of the primary end point was 12.6% in the TAVR group and 14.0% in the surgery group (95% credible interval [Bayesian analysis] for difference, -5.2 to 2.3%; posterior probability of noninferiority, >0.999). Surgery was associated with higher rates of acute kidney injury, atrial fibrillation, and transfusion requirements, whereas TAVR had higher rates of residual aortic regurgitation and need for pacemaker implantation. TAVR resulted in lower mean gradients and larger aortic-valve areas than surgery. Structural valve deterioration at 24 months did not occur in either group. CONCLUSIONS: TAVR was a noninferior alternative to surgery in patients with severe aortic stenosis at intermediate surgical risk, with a different pattern of adverse events associated with each procedure. (Funded by Medtronic; SURTAVI ClinicalTrials.gov number, NCT01586910 .).

STABLE II clinical trial on endovascular treatment of acute, complicated type B aortic dissection with a composite device design.

OBJECTIVE: To evaluate the safety and effectiveness of a composite device design (covered stent graft and bare metal stent) for the treatment of patients with acute, complicated type B aortic dissection (TBAD) presenting with aortic rupture and/or branch vessel malperfusion. METHODS: In this prospective, nonrandomized, multicenter study, 73 patients (65.8% male; mean age, 60.7 years) with acute, complicated TBAD were enrolled between August 2012 and January 2015 to receive treatment with the Zenith Dissection Endovascular System (William Cook Europe, Aps, Bjaeverskov, Denmark) at institutions in the United States and Japan. The primary safety end point was the rate of freedom from major adverse events at 30 days, and the primary effectiveness end point was the rate of survival at 30 days. This article reports primary outcomes at 30 days and follow-up results through 1 year, reflecting study data as of March 2018. RESULTS: Of 73 patients, 20 presented with aortic rupture (27%) and 57 presented with branch vessel obstruction/compromise (78%), including 4 patients presenting with both conditions. The covered stent graft was used in all patients (median, 1; range, 1-3; 1 stent graft used in 64.4%; 47/73), and the bare metal dissection stent was used in 58 of 73 patients (79.5%). Thirty-day mortality occurred in five patients (6.8%): one procedure related, three unrelated to dissection repair, and one indeterminate. Thirty-day major adverse events included myocardial infarction (1.4%), bowel ischemia (1.4%), renal insufficiency/renal failure requiring dialysis (6.8%), stroke (6.8%), paraplegia or paraparesis (5.5%), and prolonged ventilatory support (13.7%). Nine deaths occurred from 31 to 365 days (only one death related to dissection repair); the Kaplan-Meier estimate of freedom from all-cause mortality was 80.3% ± 4.7% at 1 year. Within 365 days, 9 of 73 patients (12.3%) underwent 10 secondary interventions; no patients required conversion to open surgery. At the 12-month follow-up, complete or partial thrombosis of the false lumen was seen in 100% of patients (46/46) within the stent graft region and in 97.4% of patients (38/39) within the dissection stent region. Growth (>5 mm) of the maximum transaortic diameter was observed in 14.9% of patients (7/47) in the stent graft region and in 38.5% of patients (15/39) within the dissection stent region at 12 months. CONCLUSIONS: Thirty-day and 1-year results from the STABLE II study demonstrated favorable clinical and anatomical outcomes for the treatment of rupture and malperfusion in the setting of acute, complicated TBAD. Five-year follow-up is ongoing.

Direct bridging to cardiac transplantation with the surgically implanted Impella 5.0 device.

This study evaluated outcomes of direct bridging to orthotopic heart transplantation (OHT) with the Impella 5.0 device. Adult recipients in the United Network for Organ Sharing registry bridged to OHT with the Impella 5.0 device between 2010 to 2018 were included. Outcomes included waitlist and post-transplant survival. A total of 236 patients were wait-listed with Impella 5.0 support, and 24% (n = 57) underwent bridge to OHT. Early and late post-transplant survival was excellent at 96.5% at 30 day, 93.8% at 90-day, and 90.3% at 1-year follow-up. Post-transplant complications were infrequent, but the most common were renal failure requiring dialysis (8.8%, n = 5), cerebrovascular accidents (1.8%, n = 1), and pacemaker implant (1.8%, n = 1). The rate of waitlist removal for death or clinical deterioration was 20.0% (n = 47); however, the majority of patients were bridged to OHT (24%, n = 57) or durable continuous-flow left ventricular assist device (37.0%, n = 87). The median time supported on the device, while waitlisted was 13 days (Interquartile range [IQR] 7, 20 days). The Impella 5.0 device can be used as a direct bridge to OHT with excellent survival and minimal post-transplant morbidity. Overall, these data support the utilization of Impella 5.0 as a bridge to OHT in select patients with refractory cardiogenic shock.

Off-Pump Coronary Artery Bypass Grafting: Closing the Communication Gap Across the Ether Screen.

Cardiopulmonary bypass (CPB) has been one of the most important additions to the field of heart surgery in the past century. However, significant morbidity associated with CPB has led to the increasing implementation of off-pump coronary artery bypass (OPCAB). The use of OPCAB has broadened surgical revascularization for patient populations at high risk for undergoing CPB, including the very elderly and patients with impending end-organ failure. Intraoperative hemodynamic instability requires expeditious correction of hypotension with various medical and surgical techniques that require the close attention and skill of both the anesthesia and surgical teams. Technical skill at performing and interpreting transesophageal echocardiography is essential to help differentiate regional wall motion abnormalities from coronary ischemia and external compression from manipulation of the heart, which require different management strategies to resolve hemodynamic collapse. Flawless communication between the anesthesiologist and surgeons, with frequent intraoperative adjustments, is paramount for the completion of successful OPCAB.

The effect of angiotensin-converting enzyme inhibitor exposure on coronary artery bypass grafting.

BACKGROUND: This study evaluated the impact of preoperative angiotensin-converting enzyme inhibitor (ACEi) exposure on outcomes of coronary artery bypass grafting (CABG). METHODS: Isolated CABGs from January 2010 to January 2018 at a single institution were included. Primary stratification was based on exposure to an ACEi within 48-hours of CABG. Propensity-matching with a 1:1 ratio was performed to generate cohorts with comparable baseline characteristics. Primary outcomes included operative mortality and morbidity rates as well as prolonged intensive care unit (ICU) stay. Secondary outcomes included hospital readmission. RESULTS: Five-thousand two hundred seventy propensity-matched patients underwent isolated CABG. Baseline characteristics were comparable between those exposed and unexposed to ACEi, with a Society of Thoracic Surgeons predicted risk of mortality of 2.4% in each group (P = .98). Rates of postoperative renal failure (5.0% vs 8.2%; P = .002), new-onset dialysis (1.2% vs 2.2%; P = .004), and prolonged ventilation (7.0% vs 13.4%; P < .0001) were higher in patients without ACEi exposure. The rates of prolonged ICU stay were similar (25.8% vs 27.7%; P = .127). ACEi exposed patients had lower unadjusted (1.7% vs 2.8%; P = .009) and risk-adjusted hazards for mortality at 30-days (hazard ratio, 0.59; 95% confidence interval, 0.40, 0.88; P = .01). Overall readmission rates were similar. Similar findings persisted when limiting the analysis to CABGs performed with the use of cardiopulmonary bypass. CONCLUSIONS: This study of 5270 propensity-matched patients suggests that ACEi can safely be continued until the time of CABG without an adverse impact on clinical outcomes, and in fact, may confer an early survival advantage and reduced postoperative renal failure rates.

Medical and surgical management of acute type B aortic intramural hematoma.

Type B acute aortic dissection (AAD) and intramural hematoma (IMH) can both present as potentially catastrophic lesions of the descending aorta. IMH is distinguished from AAD by the absence of an intimal tear and flap. With short-term outcomes being similar to type B AAD, IMH is treated identically to AAD in the corresponding segment of the aorta. While all patients with any acute aortic syndrome of the descending aorta receive prompt anti-impulse therapy, thoracic endovascular aortic repair (TEVAR) is reserved for patients presenting with certain complications, namely malperfusion, rupture, or periaortic hematoma. Technical aspects of TEVAR for IMH include maximal endograft oversizing of 10% with 20 mm landing zones of the healthy aorta, revascularization of the left subclavian artery when covered, use of cerebrospinal fluid drainage with extensive coverage, and restoration of branch vessel perfusion. With respect to disease evolution, IMH may progress to classic AD, frank rupture, or aneurysmal dilation; yet, IMH may also regress and be completely resorbed. However, since the natural history of IMH is unpredictable, TEVAR is being used more aggressively to improve long-term survival, rates of secondary reintervention, and positive aortic remodeling. Much remains unknown for acute type B IMH, including the use of prophylactic TEVAR for stable uncomplicated presentations, as well as the optimal timing of intervention and certain technical aspects of TEVAR. As such, IMH remains a diagnostic and therapeutic challenge for cardiovascular surgeons.

Outcomes of tissue versus mechanical aortic valve replacement in patients 50 to 70 years of age.

BACKGROUND: Societal guidelines suggest that aortic valve replacement (AVR) in patients age 50 to 70 years can be performed with either bioprosthetic or mechanical valves. This study reviewed outcomes between these valve types among patients aged 50 to 70 years undergoing AVR. METHODS: We examined adult patients 50 to 70 years undergoing isolated AVR with a mechanical or bioprosthetic valve at a single institution between 2010 and 2018. Kaplan-Meier analysis was used to evaluate longitudinal survival and multivariable Cox regression analysis was used for risk adjustment. A propensity-matched analysis was performed as well. RESULTS: A total of 723 patients underwent isolated AVR with 467 (64.6%) receiving a bioprosthetic valve. At baseline, patients undergoing bioprosthetic AVR were older (median 65 vs 60 years; P < .001). One-year survival was comparable, however, survival at 5 years was significantly higher among patients undergoing mechanical AVR (95.5% vs 82.6%; P = .010). Among the 196 matched pairs, bioprosthetic AVR was associated with an increased adjusted hazard for death (hazards ratio, 3.29; P < .001). Additionally, 5-year freedom from stroke and bleeding were similar following matching, though mechanical AVR was associated with a greater freedom from repeat valve intervention (97.5% vs 92.9%; P = .020). CONCLUSION: In patients age 50 to 70, mechanical AVR is associated with improved long-term survival and freedom from repeat aortic valve intervention. Further large cohort studies should be performed to explore the potential benefits of mechanical valve replacement in this age range.

Current trends in the management of acute type A aortic intramural hematoma.

Within the spectrum of acute aortic syndromes, intramural hematoma (IMH) is a distinct lesion that is characterized by crescentic or circumferential thickening of the aortic wall in the absence of an intimal defect. The reported incidence of IMH among all type A acute aortic syndromes ranges from 3.5% to 28.3%. As compared with acute aortic dissection, IMH is a disease of the elderly, and it tends to have reduced rates of malperfusion syndromes, aortic insufficiency, and root dilation, yet also tends to have increased rates of pericardial effusion, cardiac tamponade, and periaortic hematoma. With respect to natural history, IMH may progress to classic dissection, frank rupture, or aneurysmal dilation; yet, IMH may also regress and be completely resorbed. However, studies disagree over the rates of progression or regression; as such, few studies agree on the short-term and long-term prognosis associated with IMH. American and European guidelines advocate emergent surgery for all acutely presenting type A IMH. At a minimum, supracoronary replacement of the aorta with hemiarch reconstruction is the preferred extent of operative repair to reduce rates of long-term reintervention for disease progression. However, valve and/or root procedures may be necessary proximally, while total arch reconstruction or hybrid procedures for the descending aorta may be necessary distally. Much remains unknown for IMH, including the ideal extent of aortic repair, risk-stratification for elderly patients, and the optimal treatment paradigm for stable, uncomplicated IMH. As such, IMH remains a diagnostic and therapeutic challenge for the cardiovascular surgeon.

Outcomes of mitral valve surgery for severe ischemic mitral regurgitation.

BACKGROUND: This study evaluated outcomes of mitral valve surgery for severe ischemic mitral regurgitation (IMR). METHODS: Patients undergoing coronary artery bypass grafting (CABG) with concomitant mitral valve repair (MVr) or replacement (MVR) for severe IMR at a single center between 2010 and 2017 were included. The primary outcome was 5-year survival. Secondary outcomes included operative mortality and morbidity, hospital readmission, recurrence of at least moderate mitral regurgitation (MR), and mitral valve reoperation. RESULTS: A total of 358 patients underwent concomitant mitral valve surgery with CABG for severe IMR (275 MVr and 83 MVR). Unadjusted and risk-adjusted operative mortality was higher in MVR (16% vs 8%; P = .04). MVR patients had higher rates of postoperative renal failure, prolonged ventilation, and deep sternal wound infection. The unadjusted 5-year survival was similar (MVR 64% vs MVr 64%; P = .41), a finding that persisted after risk-adjustment. The 5-year freedom from mitral valve reoperation was 96% and 97% (P = .47). Freedom from at least moderate MR at 1-year and 3-years was 100% vs 86% (P = .09) and 100% vs 68% (P = .06) for MVR and MVr, respectively. However, only three MVr patients developed severe MR by 3 years. Cumulative hazards for all-cause readmission and heart failure-specific readmission were higher with MVR. CONCLUSIONS: Despite a trend towards higher risk of MR recurrence, patients undergoing MVr have similar rates of survival and mitral valve reoperation, with lower rates of readmission at 5-years. This, combined with lower operative mortality rates, makes MVr a reasonable choice particularly in sicker patients with higher operative risk and more limited life expectancy.

Contemporary outcomes of coronary artery bypass grafting in obese patients.

BACKGROUND: This study evaluated the impact of obesity on outcomes of coronary artery bypass grafting (CABG) with particular attention to cases using bilateral internal mammary arteries (BIMAs). METHODS: Patients undergoing isolated CABG from 2011 to 2017 at a single institution were categorized by body mass index (BMI): 18.5 to 24.9 kg/m2 , 25.0 to 29.9 kg/m2 , 30.0 to 34.9 kg/m2 , and ≥35 kg/m2 , respectively. The primary outcomes were mortality and readmission. Subgroup analysis was performed on CABGs using BIMAs. Adjusted Cox model curves were used for survival analyses and cumulative incidence function for readmissions. RESULTS: A total of 4980 patients underwent CABG with BMIs of 18.5 to 24.9 kg/m2 (17.8%; n = 884), 25.0 to 29.9 kg/m2 (35.0%; n = 1745), 30.0 to 34.9 kg/m2 (27.5%; n = 1368), and ≥35 kg/m2 (19.7%; n = 983), respectively. Patients with BMI 18.5 to 24.9 kg/m2 had a higher overall Society of Thoracic Surgeons predicted risk of mortality. Adjusted survival was similar across BMI groups, and readmission risk was highest in those with a BMI of 18.5 to 24.9 kg/m2 (P = .01). Increasing BMI was associated with higher rates of postoperative deep sternal wound infection (DSWI). CABG was performed with BIMA in 820 (16%). In patients undergoing CABG with BIMA use, there were no differences in survival, readmissions, or DSWI rates between BMI groups. CONCLUSIONS: CABG, including with the use of BIMA, can be performed in obese patients without an increased risk of mortality or hospital readmission out to 5 years. Although rates of postoperative DSWI increase with increasing BMI, this finding did not appear to be magnified in patients with BIMA, although the sample size was limited in this subanalysis. These data support the notion that BIMA use should not be precluded in the obese.

Surgical treatment of infective endocarditis: Results in 831 patients from a single center.

INTRODUCTION: This study evaluated surgical outcomes of infective endocarditis (IE), with particular attention to the impact of intravenous drug use (IVDU). METHODS: Adult patients undergoing surgery for IE between 2011 and 2018 at a single center were included and stratified by IVDU. The primary outcome was overall survival. Secondary outcomes included postoperative complications and hospital readmissions. Kaplan-Meier and multivariable Cox regression were utilized for unadjusted and risk-adjusted survival analyses, respectively. Cumulative incidence function curves were compared for hospital readmissions. RESULTS: A total of 831 patients (mean age 55 years, 34.4% female) were operated on for IE, including 318 (38.3%) with IVDU. Cultures were most commonly positive for streptococcus (25.2%), methicillin-sensitive Staphylococcus aureus (17.7%), enterococcus (14.3%), or methicillin-resistant Staphylococcus aureus (8.4%). The most common procedures included isolated aortic valve repair/replacement (18.8%), aortic root replacement (15.9%), mitral valve repair/replacement (26.7%), aortic and mitral valve replacement (8.4%), and tricuspid valve repair/replacement (7.6%). Mean follow-up was 3.4 ± 2.4 years. Overall 5-year survival was 64% and was similar between IVDU and non-IVDU. Multivariable analysis demonstrated that IVDU was not associated with mortality risk. IVDU patients displayed higher rates of all-cause readmission (61.6% vs 53.9%; P = .03), drug-use readmission (15.4% vs 1.4%; P < .001), and recurrent endocarditis readmission (33.0% vs 13.0%; P < .001). CONCLUSIONS: The majority of patients undergoing surgical treatment of IE are alive at 5-years although readmission rates are high. IVDU is not a risk factor for longitudinal mortality although patients with IVDU are at higher overall readmission risk, driven largely by greater readmissions for drug-use and recurrent endocarditis.

Temporary left ventricular assist devices as a bridge to heart transplantation.

BACKGROUND: To create equitable access to donor organs for the highest mortality patients, the cardiac transplant allocation system now prioritizes patients with surgically implanted temporary left ventricular assist devices (T-LVADs). The outcomes following a direct bridge from a T-LVAD to orthotopic heart transplant (OHT) are not well delineated. AIM: This study investigates the T-LVAD waitlist outcomes and compares the posttransplant outcomes in patients bridged to OHT with surgically implanted T-LVADs to patients bridged with durable continuous-flow left ventricular assist devices (CF-LVADs). METHODS: Adults recorded in the United Network for Organ Sharing registry bridged to OHT with a durable CF-LVAD and T-LVADs, with or without temporary right ventricular assist devices (T-RVADs), between 2010 and 2018 were included. Propensity matching and multivariable Cox regression were utilized to compare outcomes. RESULTS: Of 504 patients waitlisted with T-LVADs, the majority were transplanted (50%), bridged to CF-LVAD (17%), or recovered (9%). A total of 9047 recipients were bridged to OHT during the study period with 8875 CF-LVADs and 172 T-LVADs. Early survival in propensity-matched T-LVAD ± T-RVAD patients was similar to CF-LVAD ± T-RVAD patients but reduced at a 1-year follow-up. This difference in survival at 1-year follow-up was attributable to significantly reduced survival in patients with combined T-LVAD + T-RVAD support when compared with CF-LVAD, isolated T-LVAD and combined CF-LVAD + T-RVAD support (80% vs 90% vs 90% vs 91%; P = .005). CONCLUSIONS: This study demonstrates that most patients waitlisted with a T-LVAD are successfully bridged to durable therapy or recover, and those bridged to OHT have acceptable posttransplant outcomes, particularly when T-RVADs are not required.