Outcomes in patients with solid organ transplants undergoing cardiac surgery

OBJECTIVE

Long-term outcomes after cardiac surgery in solid organ transplant recipients are limited in the contemporary literature. The objective of this study is to evaluate postoperative outcomes in these patients, including variables associated with mortality and readmissions.

METHODS

All adults undergoing isolated coronary artery bypass grafting, isolated valve, or coronary artery bypass grafting + valve cardiac surgical procedures from 2011 to 2018 were included in this study. Patients with solid organ transplants undergoing cardiac surgery were studied. Primary outcomes included operative (30-day) and 5-year mortality.

RESULTS

A total of 11,190 patients underwent isolated coronary artery bypass grafting, isolated valve, or coronary artery bypass grafting + valve operations at our institution from 2011 to 2018. Of these, 129 patients (1%) had solid organ transplants and underwent isolated coronary artery bypass grafting (n = 84), isolated valve (n = 30), or coronary artery bypass grafting + valve (n = 15). Type of organ transplant included 84 patients (65%) with kidney, 27 patients (21%) with liver, 9 patients (7%) with heart, and 9 patients (7%) with lung transplants. The median Society of Thoracic Surgeons Predicted Risk Of Mortality for the cohort was 2.73 (Q1-Q3: 1.67-6.33). Three patients (2%) had an operative (30-day) mortality. Significant variables associated with 5-year mortality on multivariable Cox regression analysis included chronic obstructive pulmonary disease (hazard ratio, 2.44; 1.01-5.90; P = .048) and congestive heart failure (hazard ratio, 4.45; 1.81-10.9; P = .001). Significant variables associated with 5-year readmissions included chronic obstructive pulmonary disease, dialysis dependence, and concomittant valve surgery with coronary artery bypass grafting. Five-year readmission rate was 88%, and patients with valve operations (± coronary artery bypass grafting) had significantly lower (P = .009) freedom from readmission (6%).

CONCLUSIONS

Cardiac surgery can be performed with low operative mortality and good long-term survival in patients with solid organ transplants. Five-year hospital readmissions are common, with significantly more readmissions in patients who had valve procedures.

The American Association for Thoracic Surgery consensus guidelines on bicuspid aortic valve-related aortopathy: Full online-only version

Bicuspid aortic valve disease is the most common congenital cardiac disorder, being present in 1% to 2% of the general population. Associated aortopathy is a common finding in patients with bicuspid aortic valve disease, with thoracic aortic dilation noted in approximately 40% of patients in referral centers. Several previous consensus statements and guidelines have addressed the management of bicuspid aortic valve-associated aortopathy, but none focused entirely on this disease process. The current guidelines cover all major aspects of bicuspid aortic valve aortopathy, including natural history, phenotypic expression, histology and molecular pathomechanisms, imaging, indications for surgery, surveillance, and follow-up, and recommendations for future research. It is intended to provide clinicians with a current and comprehensive review of bicuspid aortic valve aortopathy and to guide the daily management of these complex patients.

Neurological Complications After Transcatheter Versus Surgical Aortic Valve Replacement in Intermediate-Risk Patients

BACKGROUND

Neurological events after aortic valve interventions are associated with increased mortality and morbidity. Transcatheter aortic valve replacement (TAVR) is increasingly offered for lower-risk patients with severe aortic stenosis, previously considered candidates for surgical aortic valve replacement (SAVR). Differences in post-procedural neurological events have important implications in treatment allocation.

OBJECTIVES

The authors sought to analyze the neurological events in the randomized SURTAVI (Surgical Replacement and Transcatheter Aortic Valve Implantation) trial.

METHODS

Patients with severe, symptomatic aortic stenosis at intermediate surgical risk were randomized 1:1 to TAVR or SAVR. The rates of neurological events and quality of life were analyzed at 30 days, and 6 and 12 months post-procedure in a modified intention-to-treat population (mean age 79.8 ± 6.2 years; N = 1,660).

RESULTS

The rates of early (30-day) stroke and post-procedural encephalopathy were higher after SAVR versus TAVR (5.4% vs. 3.3%; p = 0.031; and 7.8% vs. 1.6%; p < 0.001, respectively). At 12 months, the rate of stroke was not different between SAVR and TAVR (6.9% vs. 5.2%; p = 0.136). Early stroke and early encephalopathy resulted in an elevated mortality at 12 months in both treatment groups. Quality of life after an early stroke was significantly lower in SAVR versus TAVR patients at 30 days and was similar at 6 and 12 months.

CONCLUSIONS

The early stroke rate was lower after TAVR than SAVR. In patients with early strokes, QOL improved earlier after TAVR. At 12-month follow-up, stroke rates and QOL were not different between TAVR and SAVR patients. (Surgical Replacement and Transcatheter Aortic Valve Implantation [SURTAVI]; NCT01586910).

Medical student perceptions of a career in cardiothoracic surgery: Results of an institutional survey

OBJECTIVES

Recruiting medical students to cardiothoracic surgery is critical given new training paradigms and projected cardiothoracic surgeon shortages. This study characterizes current perceptions and exposure to cardiothoracic surgery among all levels of medical students.

METHODS

Currently active medical students at all levels at a US allopathic medical school were sent an invitation to complete an online survey. Baseline demographics, medical specialty interest, interest and exposure to cardiac surgery specifically, and awareness of procedures performed by cardiothoracic surgeons were evaluated. Five-point Likert scales were used to evaluate attitudes toward facets of the field of cardiothoracic surgery. Only complete surveys over the 4-week enrollment period were used for analysis.

RESULTS

There were 126 surveys (22%) completed during the study period. Interest in cardiothoracic surgery at any point was indicated by 37% of students, but only 13% indicated an interest at the time of the survey. Interest among first-year students was greater than all other classes (30% vs <15%, P = .02). Lifestyle factors and personal attributes of cardiothoracic surgeons were noted as negative factors influencing cardiothoracic surgery perception, whereas intellectual challenge and clinical impact were cited as positive factors. Increasing interaction with faculty/residents and simulation experiences were factors noted to increase interest in the field.

CONCLUSIONS

Although medical students report early interest in cardiothoracic surgery because of intellectual stimulation and patient care attributes, lack of early exposure and perceived poor lifestyle negatively affect interest in the field. Early interaction between students and cardiothoracic faculty/trainees along with early exposure opportunities may increase recruitment.

Mechanical versus bioprosthetic valves in patients on dialysis

Background

The aim of this study is to evaluate the outcomes of bioprosthetic versus mechanical valves in patients on dialysis.

Methods

All patients who underwent aortic (AVR) or mitral valve replacement (MVR) at a single institution from 2011-2017 were reviewed. Primary stratification was bioprosthetic versus mechanical valves. The primary outcome was all-cause mortality. Secondary outcomes included hospital readmission, valve reoperation rates and bleeding events. Kaplan-Meier curves were generated and Cox proportional hazards regression models were used for risk-adjustment.

Results

During the study period, 3,969 patients underwent AVR or MVR, of which 97 (2.4%) were on dialysis. In dialysis patients, unadjusted 30-day mortality was comparable between bioprosthetic (12.7%) versus mechanical (5.9%) valves (P=0.31). However, the bioprosthetic group had higher rates of 1-year (40.3% versus 15.2%; P=0.03) and 5-year mortality (67.9% versus 60.7%; P=0.02). Most patients were readmitted within 5 years with no differences between the groups (bioprosthetic 80.3% versus mechanical 100%; P=0.57). There were no valve reoperations in either group at 5 years. The 5-year readmission rate was higher in the mechanical cohort (10.5% versus 53.8%; P=0.05). Risk-adjusted analysis confirmed these findings, where mechanical valves were independently associated with reduced mortality at 1-year and 5-years.

Conclusions

Despite the limited life expectancy of patients on dialysis, mechanical valves have an intermediate term mortality benefit compared to bioprosthetic valves. This comes at the expense of a higher rate of readmission for bleeding. Although valve choice should consider multiple factors, these data suggest that mechanical valve usage in dialysis patients is reasonable.

Distal Extent of Surgery for Acute Type A Aortic Dissection

Acute type A aortic dissection (TAAD) is a complex disease associated with extremely high morbidity and mortality for which we advocate a coordinated, protocol-driven system of care delivery that begins at patient diagnosis and continues throughout and beyond aortic reconstruction. Essential components of TAAD repair include prompt restoration of true lumen blood flow with obliteration of the false lumen flow, resection of the primary tear sites, restoration of valvular competency, and elimination of any organ malperfusion. This article focuses specifically on extent of repair of the aortic arch and explains our protocols regarding cannulation location and technique, cerebral and distal organ protection strategy, management of the brachiocephalic vessels, and extent of distal aortic reconstruction. We describe an operative strategy for TAAD repair that includes (1) continuous neurocerebral monitoring in all cases, (2) uninterrupted antegrade and/or retrograde cerebral perfusion (depending upon extent of arch repair) during open arch reconstruction, (3) aortic arch replacement technique with or without brachiocephalic vessel replacement using a custom trifurcate graft, and (4) descending aortic stabilization with or without the use of an elephant or frozen elephant trunk (distal stent graft). Our protocol for extent of aortic arch and brachiocephalic reconstruction has been standardized and is predicated on distinct pathoanatomic findings and/or cerebral malperfusion that are outlined.

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.).

Endovascular management of spontaneous rupture of the left subclavian artery

Spontaneous rupture of the left subclavian artery is a rare condition that requires immediate surgical intervention. A 21-year-old man with a history of membranoproliferative glomerulonephritis, failed kidney transplant, and history of a type A aortic dissection that was surgically repaired was admitted with altered mental status and hypotension. He was found to have a left subclavian artery rupture. This was successfully managed with emergent thoracic endovascular aortic repair and carotid-subclavian bypass.

Clinical outcomes and hospital readmission rates in mechanical vs bioprosthetic mitral valves

OBJECTIVE

Recent national trends have demonstrated increased use of bioprosthetic mitral valves. The primary objective of this study was to compare clinical outcomes as well as readmission rates for mechanical vs bioprosthetic mitral valve replacement (mMVR vs bMVR).

METHODS

All patients undergoing MVR from 2011-2017 were included in a single center data set that was obtained retrospectively from a prospectively maintained cardiac surgical database.

RESULTS

The total MVR patient cohort consisted of 828 patients, including bMVR (n = 522) and mMVR (n = 306). There was no significant difference in the operative (30-day) mortality between bMVR and mMVR (8.6% vs 6.5%; P = .31). The unadjusted estimated 1-year mortality was significantly higher for the bMVR group (19.8% vs 13.7%, P = .04) and this trend continued for the estimated 5-year mortality (35.1% vs 18.7%; P = .001). Valve prosthesis choice (bMVR vs mMVR) did not have a risk-adjusted impact on operative mortality at 30 days (P = .58); however 1-year (P = .05) and 5-year (P = .05) mortality remained significantly higher for the bMVR group. Propensity matching revealed a higher mortality rate on follow-up in the bMVR (26.7% vs 18.2%, P = .03) but no difference at 30 days or 1 year. There was no difference in hospital readmissions over 5 years CONCLUSIONS: Mechanical prostheses may confer a survival benefit in patients undergoing MVR. With emphasis on patient education and anticoagulation compliance, mMVR remains an efficacious option.

Insights From the International Registry of Acute Aortic Dissection: A 20-Year Experience of Collaborative Clinical Research

Acute aortic dissection (AAD) is a life-threatening condition associated with high morbidity and mortality rates, and it remains a challenge to diagnose and treat. The International Registry of Acute Aortic Dissection was established in 1996 with the mission to raise awareness of this condition and provide insights to guide diagnosis and treatment. Since then, >7300 cases have been included from >51 sites in 12 countries. Although presenting symptoms and physical findings have not changed significantly over this period, the use of computed tomography in the diagnosis has increased, and more patients are managed with interventional procedures: surgery in type A AAD and endovascular therapy in type B AAD; with these changes in care, there has been a significant decrease in overall in-hospital mortality in type A AAD but not in type B AAD. Herein, we summarized the key lessons learned from this international registry of patients with AAD over the past 20 years.

Longitudinal Outcomes of Women Undergoing Transcatheter Aortic Valve Replacement

OBJECTIVE

Recent data have suggested that women have a survival benefit at 1-year follow-up. However, long-term gender-based TAVR outcomes are lacking.

METHODS

All patients undergoing isolated TAVR from 2011 to 2017 were included. Patients were stratified by gender. The primary outcomes of the study were 3-year mortality and 3-year hospital readmissions. Multivariable logistic regression analysis was used to evaluate the risk-adjusted impact of gender on TAVR outcomes.

RESULTS

A total of 1,036 patients were divided into male (n = 518) and female (n = 518) cohorts. Women had a borderline significantly increased STS PROM (8.3% ± 5 vs. 7.7% ± 4.4; P = 0.05). The majority of procedures were performed under conscious sedation (male: 89% vs. female: 88%; P = 0.62) and via transfemoral access (male: 81.8% vs. female: 81.4%; P = 0.46). There was no difference in operative (30-day) mortality (male: 15 [3.3%] vs. female: 17 [3.7%]; P = 0.77) or 30-day readmissions (male: 40 [10.8%] vs. female: 44 [12.2%]; P = 0.56). Perioperative blood product usage was higher for women (male: 8.1% vs. female: 14.1%; P = 0.002). There was no significant difference in major vascular complications (male: 0.4% vs. female: 1.0%; P = 0.26) or major bleeding (male: 0.2% vs. female: 0.4%; P = 0.56). Permanent pacemaker placement was higher for males (11.6% vs. 7.0%; P = 0.01). On risk-adjusted multivariable analysis, gender was not a factor associated with mortality (HR 0.99 [0.76 to 1.30]; P = 0.99) or readmission (HR 0.90 [0.72 to 1.14]; P = 0.42) at 5 years.

CONCLUSIONS

There was no difference in survival or readmissions on multivariable analysis for women undergoing TAVR at 3 years. Longitudinal multi-institutional data will be important to validate these findings.

Coronary Bypass Versus Percutaneous Revascularization in Multivessel Coronary Artery Disease

BACKGROUND

This study focused on contemporary outcomes after coronary artery bypass graft (CABG) surgery versus percutaneous coronary intervention (PCI) in patients with multivessel coronary artery disease (MVCAD).

METHODS

This was a propensity-matched retrospective, observational analysis. Patients with MVCAD who underwent CABG or PCI between 2010 and 2018 and for whom data were available through the National Cardiovascular Data Registry or The Society of Thoracic Surgeons Adult Cardiac Surgery Database were included. The primary outcome was overall survival. Secondary outcomes included freedom from inpatient readmission and freedom from repeat revascularization.

RESULTS

Of the initial 6,163 patients with MVCAD, the propensity-matched cohort included 844 in each group. The estimated 1-year mortality was 11.5% and 7.2% (p < 0.001) in the PCI and CABG groups, respectively, with an overall hazard ratio for mortality of PCI versus CABG of 1.64 (95% confidence interval [CI], 1.29 to 2.10; p < 0.001). The overall hazard ratio for readmission for PCI versus CABG was 1.42 (95% CI, 1.23 to 1.64; p < 0.001). The overall hazard ratio for repeat revascularization for PCI versus CABG was 4.06 (95% CI, 2.39 to 6.91; p < 0.001). Overall major adverse cardiovascular events and individual outcomes of mortality, readmission, and repeat revascularization all favored CABG across virtually all major clinical subgroups.

CONCLUSIONS

This contemporary propensity-matched analysis of patients undergoing coronary revascularization for MVCAD demonstrates a significant mortality benefit with CABG over PCI, and this benefit is consistent across virtually all major patient subgroups. Futures studies are needed reflecting routine practice to assess how best to approach shared decision making and informed consent when it comes to revascularization decisions in any patient with MVCAD.

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.).

Diagnostic dilemma in prosthetic valve endocarditis: Computed tomography to the rescue

A 58-year-old man with multiple myeloma, prior bioprosthetic valve, spinal hardware and multiple episodes of Corynebacterium amycolatum bacteremia was found to have a well-seated valve without vegetations, paravalvular leak, abscess or degeneration over a period of 6 months on five separate transesophageal echocardiographic studies. Computed tomography angiography was performed which revealed vegetation at the level of the left ventricular outflow tract. Reoperative sternotomy and interrogation of the valve confirmed a 1.5-cm vegetation with the same bacterium. The patient underwent a redo aortic valve replacement and recovered without any complications. He has been asymptomatic and culture negative on surveillance.