Surgical Outcomes of Septal Myectomy With and Without Mitral Valve Surgeries in Hypertrophic Cardiomyopathy: a National Propensity-Matched Analysis (2005 to 2020)

The management of concomitant mitral valve (MV) disease in patients with hypertrophic cardiomyopathy (HCM) remains controversial. The 2020 American Heart Association/American College of Cardiology HCM guidelines recommend that MV replacement (MVR) at the time of myectomy should not be performed for the sole purpose of relieving outflow obstruction. At the national level, limited data exist on the surgical outcomes of MV repair/replacement in patients with HCM who underwent septal myectomy (SM). Hospitalizations of patients with HCM who underwent SM between 2005 and 2020 were identified using International Classification of Diseases, Ninth and Tenth Revision codes (International Classification of Diseases, Ninth and Tenth Revision Clinical Modification/Procedure Coding System). The 3 comparison cohorts were SM alone, MV repair, and MVR with concomitant SM. After propensity matching, 2 cohorts, SM + MVR versus SM + MV repair, were studied for surgical outcomes. Demographic characteristics, baseline co-morbidities, procedural complications, inpatient mortality, length of stay, and cost of hospitalization were compared between the propensity-matched cohorts. A total of 16,797 SM procedures were identified from 2005 to 2020. Among them, 11,470 hospitalizations had SM alone (68.2%), SM + MVR was seen in 3,101 (18.4%), and SM + MV repair comprised 2,226 (13.2%). After propensity matching, the MVR and MV repair formed the matched cohorts of 1,857. There were no significant differences in the odds of cardiogenic shock (adjusted odds ratio [aOR] 0.88, 95% confidence interval [CI] 0.63 to 1.24, p = 0.49), mechanical circulatory support requirement (aOR 0.58, 95% CI 0.37 to 0.90, p = 0.015), stroke (aOR 1.27, 95% CI 0.81 to 1.99, p = 0.29), and major bleeding (aOR 0.52, 95% CI 0.34 to 0.79, p = 0.0026) between the comparison groups. MVR, compared with MV repair, was associated with a higher risk of procedural mortality (8.02% vs 3.18%, aOR 2.98, 95% CI 2.05 to 4.33, p <0.0001), complete heart block (16.36% vs 12.15%, aOR 1.76, 95% CI 1.44 to 2.12, p <0.0001), and the need for permanent pacemaker (16.39% vs 10.62%, aOR 1.83, 95% CI 1.41 to 2.38, p <0.0001). The total length of hospital stay and median hospitalization cost was higher in the MVR group. SM in HCM concomitant with MVR is associated with higher procedural mortality and in-hospital complication risk. These real-world data support the 2020 American Heart Association/American College of Cardiology guidelines that in patients who are candidates for surgical myectomy, MVR should not be performed as part of the operative strategy for relieving outflow obstruction in HCM.

Effect of concurrent mitral valve surgery for secondary mitral regurgitation upon mortality after aortic valve replacement or coronary artery bypass surgery

Objectives

It is uncertain whether concurrent mitral valve repair or replacement for moderate or greater secondary mitral regurgitation at the time of coronary artery bypass graft or aortic valve replacement surgery improves long-term survival.

Methods

Patients undergoing coronary artery bypass graft and/or aortic valve replacement surgery with moderate or greater secondary mitral regurgitation were reviewed. The effect of concurrent mitral valve repair or replacement upon long-term mortality was assessed while accounting for patient and operative characteristics and mitral regurgitation severity.

Results

Of 1,515 patients, 938 underwent coronary artery bypass graft or aortic valve replacement surgery alone and 577 underwent concurrent mitral valve repair or replacement. Concurrent mitral valve repair or replacement did not alter the risk of postoperative mortality for patients with moderate mitral regurgitation (hazard ratio = 0.93; 0.75-1.17) or more-than-moderate mitral regurgitation (hazard ratio = 1.09; 0.74-1.60) in multivariable regression. Patients with more-than-moderate mitral regurgitation undergoing coronary artery bypass graft-only surgery had a survival advantage from concurrent mitral valve repair or replacement in the first two postoperative years (P = 0.028) that did not persist beyond that time. Patients who underwent concurrent mitral valve repair or replacement had a higher rate of later mitral valve operation or reoperation over the five subsequent years (1.9% vs. 0.2%; P = 0.0014) than those who did not.

Conclusions

These observations suggest that mitral valve repair or replacement for more-than-moderate mitral regurgitation at the time of coronary artery bypass grafting may be reasonable in a suitably selected coronary artery bypass graft population but not for aortic valve replacement, with or without coronary artery bypass grafting. Our findings are supportive of 2021 European guidelines that severe secondary mitral regurgitation "should" or be "reasonabl[y]" intervened upon at the time of coronary artery bypass grafting but do not support 2020 American guidelines for performing mitral valve repair or replacement concurrent with aortic valve replacement, with or without coronary artery bypass grafting.

Joint preoperative transthoracic and intraoperative transoesophageal echocardiographic assessment of functional mitral regurgitation severity provides better association with long-term mortality

OBJECTIVES

Functional mitral regurgitation (MR) is observed with ischaemic heart disease or aortic valve disease. Assessing the value of mitral valve repair or replacement (MVR/P) is complicated by frequent discordance between preoperative transthoracic echocardiographic (pTTE) and intraoperative transoesophageal echocardiographic (iTOE) assessment of MR severity. We examined the association of pTTE and iTOE with postoperative mortality in patients with or without MR, at the time of coronary artery bypass grafting (CABG) and/or aortic valve replacement without MVR/P.

METHODS

Medical records of 6629 patients undergoing CABG and/or aortic valve replacement surgery with or without functional MR and who did not undergo MVR/P were reviewed. MR severity assessed by pTTE and iTOE were examined for association with postoperative mortality using proportional hazards regression while accounting for patient and operative characteristics.

RESULTS

In 72% of 709 patients with clinically significant (moderate or greater) functional MR detected by pTTE, iTOE performed after induction of anaesthesia demonstrated a reduction in MR severity, while 2% of patients had increased severity of MR by iTOE. iTOE assessment of MR was better associated with long-term postoperative mortality than pTTE in patients with moderate MR [hazard ratio (HR) 1.31 (1.11-1.55) vs 1.02 (0.89-1.17), P-value for comparison of HR 0.025] but was not different for more than moderate MR [1.43 (0.96-2.14) vs 1.27 (0.80-2.02)].

CONCLUSIONS

In patients undergoing CABG and/or aortic valve replacement without MVR/P, these findings support intraoperative reassessment of MR severity by iTOE as an adjunct to pTTE in the prediction of mortality. Alone, these findings do not yet provide evidence for an operative strategy.

Enhanced Recovery After Cardiac Surgery: A Propensity-Matched Analysis

Enhanced Recovery After Surgery (ERAS) pathways have improved clinical outcomes, cost-effectiveness, and patient satisfaction across multiple non-cardiac surgical specialties. Since the adaptation of ERAS in cardiac surgery is rapidly increasing yet still evolving, herein, we demonstrate early results of our implementation of ERAS cardiac guidelines. We retrospectively reviewed all patients who were managed with our institutional ERAS Cardiac Surgery guidelines between 5/2018 and 6/2019(N = 102). Postoperative primary outcomes (total ventilation times(hours), intensive-care unit(ICU) stay, and postoperative hospital length of stay (LOS)) were compared to 1:1 propensity matched controls from the pre ERAS era between January 2017 and March 2019. A total of 76 propensity-matched pairs were identified. Compared to the matched controls, ERAS patients had significantly shorter median ventilation times(3.5 vs. 5.3 hours, p = .01), ICU stays(median 28 vs 48 hours, p=.005) and postoperative hospital LOS (median 5 vs. 6 days, p = .03). There were no operative mortalities and no significant differences in 30-day readmission rates. There were also no significant differences in post-operative stroke, acute kidney injury, atrial fibrillation, and reoperation rates for bleeding. Two-year survival was also not statistically different between the two cohorts (p = .22). Our initial experience with implementation of ERAS protocols in cardiac surgery appear to demonstrate that these protocols are associated with shorter ventilation times, ICU stay, and hospital LOS without compromising patient outcomes. While these results are promising yet preliminary, further studies are warranted to demonstrate whether ERAS algorithms in cardiac surgery can consistently expedite postoperative recovery and improve outcomes.

Surgical Aortic Valve Replacement Outcomes in Non-TAVR Centers - Implications to Tier-Based Systems of Care

BACKGROUND

With wide expansion of Transcatheter aortic valve replacement (TAVR) and dissemination of multidisciplinary-based approaches to care, societies are discussing the implementation of a Tier-system to valve centers. This study explores the impact of Tier-based systems of care on Surgical AVR (SAVR) outcomes at institutions that perform SAVR only.

METHODS

Medicare beneficiaries undergoing SAVR procedures from 2012 - 2015 were included. SAVR Hospitals were stratified into either Tier A, valve centers with a TAVR program, and Tier B, valve centers without a TAVR program. Adjusted survival, assessed by multivariable Cox regression, controlled for program type and patient risk-profile. Time-dependent analysis accounted for hospitals that initiated a TAVR program during the study period.

RESULTS

Overall, there were 562 Tier A and 485 Tier B SAVR hospitals. Tier A hospitals had significantly higher comorbidity burden compared to Tier B hospitals (all P<0.05) but had significantly lower rates of 30-day mortality (3.2% vs 4.1%) and 1-year mortality (8.1% vs 9.4%; both P<0.05). After risk stratification, Tier B hospitals had significantly worse 30-day mortality compared to Tier A hospitals for all patient risk-profiles, except for the low-risk patients (P<0.01). These findings persisted in the time-dependent analysis. Adjusted mid-term survival was higher in Tier A versus Tier B hospitals.

CONCLUSIONS

Low-risk patients can safely undergo SAVR in both Tier levels without compromising outcomes. Establishment of quality of care measures, especially in the SAVR-only hospitals, remains paramount and should be closely integrated when designing Tier-based systems for AVR care.

Long-term Outcomes of Aortic Valve Replacement With Aortic Homograft: 27 Years Experience

BACKGROUND

Aortic homografts have been used in young patients requiring aortic valve replacement. Currently, these grafts are generally reserved for aortic valve endocarditis with or without root abscess; however, longitudinal data are lacking. Our aim was to assess the long-term safety and durability of homograft implantation.

METHODS

All adult patients undergoing aortic homograft implantation at a single institution from 1992 to 2019 were included. Outcomes of interest included all-cause mortality and aortic valve reoperation, studied over a median follow-up duration of 19 years.

RESULTS

In all, 252 patients with a mean age of 49 years were included. Infective endocarditis was the primary indication for surgery in 95 patients (38%). The endocarditis group, compared with the no-endocarditis group, had a higher prevalence of New York Heart Association class III-IV (56% vs 26%), chronic kidney disease (22% vs 1%), prior cardiac surgery (40% vs 10%), and emergency status (7% vs 0%; all P < .001). Operative mortality was higher among endocarditis patients (16% vs 0.6%, P < .001), which persisted after risk adjustment. Among patients who survived to discharge, however, there was no difference in long-term survival between the endocarditis group and no-endocarditis group. Overall survival and freedom from reoperation were 88.3% and 80% at 15 years and 87.2% and 78% at 25 years, respectively. Indications for reoperation included structural valve deterioration (83%), endocarditis (12%), and mitral valve disease (5%). Reoperative mortality occurred in 2 patients (4.9%).

CONCLUSIONS

Aortic homografts are associated with good long-term survival and admissible freedom from reoperation. Operative mortality is high among patients with endocarditis; however, for those who survive to discharge, long-term survival and durability are the same as for patients without endocarditis.

Wound complications and 30-day readmissions after single and bilateral internal mammary grafting: Analysis of the Nationwide Readmissions Database

BACKGROUND

This study compares the postoperative outcomes, 30-day readmission rates, and incidence of sternal wound infection-related readmissions between patients receiving bilateral internal mammary arteries (BIMA) and single internal mammary artery (SIMA) grafting during coronary artery bypass graft (CABG) surgery.

METHODS

We utilized the weighted 2013-2014 National Readmission Database claims to identify all US adult patients who underwent CABG utilizing SIMA (n = 279,891) or BIMA (n = 11,651). Thirty-day overall and wound-related readmissions, in-hospital outcomes, costs, lengths of stay (LOS) at readmissions were compared between the two groups. Predictors of 30-day readmission were assessed using multivariable Cox proportional hazards analysis.

RESULTS

After propensity matching (n = 10,339 pairs), there were no significant differences between the two groups during the index hospitalization, except for higher total hospital costs in the BIMA group (p = .02). The incidence of wound infections was also comparable between BIMA and SIMA (1.1% vs. 1.2%; p = .50). At 30-days, the overall readmission rate was elevated in SIMA patients (9.5% vs. 8.8%; p < .01), primarily impacted by cardiovascular causes. While the proportion of 30-day readmissions due to infections was significantly higher among BIMA versus SIMA patients (20.4% vs. 15.9%; p < .01), wound infections during the index hospitalization did not predict all-cause 30-day readmission among BIMA patients (p = .24) in the risk-adjusted analysis. Among the readmitted patients, LOS (6.4 vs. 6.2 days), costs ($14,440 vs. $16,461), and in-hospital mortality (2.4% vs. 1.7%) were comparable between the two groups (all p > .05).

CONCLUSIONS

BIMA grafting is not an independent predictor of all-cause 30-day readmissions. Cardiovascular causes remain the primary driver of 30-day readmissions among SIMA and BIMA patients after CABG.

Subclinical Structural Valve Degeneration in Young Patients With Bioprosthetic Aortic Valves

BACKGROUND

Bioprosthetic structural valve degeneration (SVD) has previously been a clinical diagnosis, but subclinical changes have been increasingly recognized in transcatheter valves. The significance of subclinical SVD after surgical aortic valve replacement (SAVR), however, is not well understood. The purpose of this study was to characterize the incidence and outcomes of subclinical SVD in young patients after SAVR.

METHODS

Patients aged ≤65 years who underwent bioprosthetic SAVR between January 2002 and June 2018 at a single institution were included. Endocarditis cases and those with in-hospital mortality were excluded. All available longitudinal postoperative echocardiograms were reviewed. Subclinical SVD was defined as an increase in mean transvalvular gradient of at least 10 mm Hg and/or new onset of mild intraprosthetic regurgitation or increase by at least 1 grade, compared with baseline postoperative echocardiogram.

RESULTS

Overall, 822 unique SAVR cases were included. Over the study period, 356 (43.3%) patients developed subclinical SVD. Only 21.5% of those with subclinical SVD progressed to clinical SVD or to repeat aortic valve procedures. In those with progression, the first signs of SVD occurred significantly earlier than in those whose changes remained stable (11 months vs 23 months; P = .036). Anticoagulation did not impact the development or progression of subclinical SVD. There was no difference in long-term survival for those who did or did not develop subclinical SVD.

CONCLUSIONS

Subclinical SVD occurred in a large proportion of young patients undergoing bioprosthetic SAVR. Despite its high prevalence, subclinical SVD was not associated with decreased survival or repeat procedures.

Systemic Allergic Contact Dermatitis Due to a GORE CARDIOFORM Septal Occluder Device: A Case Report and Literature Review

Nickel hypersensitivity is a rarely reported complication of percutaneous patent foramen ovale/atrial septal defect closure. Herein, we report a case of systemic allergic contact dermatitis to nickel present in a GORE CARDIOFORM (W.L. Gore, Flagstaff, Arizona) septal occluder that resolved following explanation. To our knowledge this is the first published case of nickel hypersensitivity associated with this device. (Level of Difficulty: Beginner.)

The impact of hospital size on national trends and outcomes in isolated open proximal aortic surgery

OBJECTIVE

To determine the impact of hospital size on national trend estimates of isolated open proximal aortic surgery for benchmarking hospital performance.

METHODS

Patients age >18 years who underwent isolated open proximal aortic surgery for aneurysm and dissection from 2002 to 2014 were identified using the National Inpatient Sample. Concomitant valvular, vessel revascularization, re-do procedures, endovascular, and surgery for descending and thoracoabdominal aorta were excluded. Discharges were stratified by hospital size and analyzed using trend, multivariable regression, propensity-score matching analysis.

RESULTS

Over a 13-year period, 53,657 isolated open proximal aortic operations were performed nationally. Although the total number of operations/year increased (∼2.9%/year increase) and overall in-hospital mortality decreased (∼4%/year; both P < .001 for trend), these did not differ by hospital size (P > .05). Large hospitals treated more sicker and older patients but had shorter length of stay and lower hospital costs (both P < .001). Even after propensity-score matching, large hospital continued to demonstrate superior in-hospital outcomes, although only statistically for major in-hospital cardiac complications compared with non-large hospitals. In our subgroup analysis of dissection versus non-dissection cohort, in-hospital mortality trends decreased only in the non-dissection cohort (P < .01) versus dissection cohort (P = .39), driven primarily by the impact of large hospitals (P < .01).

CONCLUSIONS

This study demonstrates increasing volume and improving outcomes of isolated open proximal aortic surgeries nationally over the last decade regardless of hospital bed size. Moreover, the resource allocation of sicker patients to larger hospital resulted shorter length of stay and hospital costs, while maintaining similar operative mortality to small- and medium-sized hospitals.

Transcatheter vs surgical aortic valve replacement in patients with interstitial lung disease

BACKGROUND

Patients with underlying interstitial lung disease (ILD) who undergo cardiac surgery are at high risk of postoperative pulmonary complications. It remains unclear if transcatheter aortic valve replacement (TAVR) offers any benefit over surgical aortic valve replacement (SAVR) in ILD patients with severe aortic stenosis.

METHODS

All adult patients with a diagnosis of ILD who underwent either a TAVR or isolated SAVR between January 2002 and December 2017 were retrospectively reviewed. Operative mortality, 30-day readmissions, and adjusted 1-year survival were compared between the two cohorts.

RESULTS

The overall cohort included 52 TAVR and 74 SAVR patients. While TAVR patients were significantly older (77.2 vs 72.9 years) with higher Society of Thoracic Surgeons predicted risk of mortality (STS-PROM) scores compared with SAVR patients (6.29 vs 4.49; all P < .02), operative mortality was similar (5.8% vs 4.1%; P =  .45). Rates of postoperative stroke, permanent pacemaker implantation, reintubation, and 30-day readmissions did not differ between the two groups (all P > .46). However, TAVR was associated with significantly shorter hospital and intensive care unit (ICU) length of stay, shorter ventilation times, and less requirement for ICU admission (all P < .05). Thirty-day readmissions and adjusted 1-year survival were also similar between the two groups (hazard ratio for TAVR vs SAVR = 1.34; 95% CI: 0.7-2.6).

CONCLUSIONS

Among ILD patients with symptomatic aortic stenosis, TAVR was associated with comparable operative and risk-adjusted 1-year survival to SAVR. TAVR patients also had shorter ventilator times, ICU and hospital stay despite being at higher risk. Together, our findings suggest that TAVR may be a better option in this unique cohort.

Long-Term Outcomes of Right Minithoracotomy Versus Hemisternotomy for Mitral Valve Repair

OBJECTIVE

Minimally invasive mitral valve repair has been increasingly adopted. Right minithoracotomy (RT) and lower hemisternotomy (HS) have each been associated with improved short-term outcomes; however, these approaches have not been directly compared to each other. The aim of this study was to compare long-term survival and durability of 2 minimally invasive approaches to mitral repair.

METHODS

We retrospectively identified all isolated mitral repairs performed via RT or HS between October 1997 and June 2018; 100 RT cases and 719 HS cases were included. Outcomes of interest were postoperative complications, long-term survival, and freedom from mitral reoperation. A Cox proportional hazard model was used to compare RT and HS to a reference cohort of full-sternotomy cases. Total observation time was 9,901 patient-years and mean follow-up time was 12.2 years.

RESULTS

Mean age was 58±12 years in the RT group and 56±13 years in the HS group (P = 0.2). The RT group had longer bypass (143 minutes vs. 112 minutes; P < 0.001) and cross-clamp times (99 minutes vs. 78 minutes; P < 0.001) compared with the HS group. There were no differences in operative mortality or 30-day outcomes. Survival at 5, 10, and 15 years was 99% (96-100), 92% (85-100), and 69% (30-100) in the RT group and 98% (97-99), 92% (90-94), and 89% (86-92) for HS (P < 0.9). There were no differences in risk-adjusted survival between RT, HS and full sternotomy. No long-term mitral reoperations occurred in the RT group and 8 (1%) occurred in the HS group (P < 0.50).

CONCLUSIONS

Minimally invasive mitral valve repair can be performed safely through RT or HS with excellent survival and durability at 15 years.

Early and Midterm Outcomes of Valve-Sparing Aortic Root Replacement-Reimplantation Technique

Background  Valve-sparing aortic root replacement (VSARR) is an increasingly popular alternative to traditional aortic root replacement for aortic root aneurysm disease with a normal aortic valve. We evaluated the early and midterm outcomes of VSARR—reimplantation technique (VSARR-RT) done at a single institution over a decade.

Materials and Methods  We performed a retrospective study of all patients who underwent VSARR-RT between January 2004 and July 2014.

Results A total of 85 patients underwent VSARR-RT. Median time to latest echocardiographic follow-up was 4 years (range: 15–72 months). Total observation time was 491 patient years. Mean age was 44.6 ± 14.3 years, and 13 (15%) were women. Thirty-nine (46%) patients had a connective tissue disorder and 6 (7%) had a bicuspid aortic valve. Thirty-three (39%) patients underwent concomitant procedures, including coronary artery bypass grafting ( n  = 9, 11%), mitral valve repair ( n  = 8, 9%), and aortic hemi-arch replacement ( n  = 7, 8%). There were no operative deaths or in-house mortality and no postoperative strokes. Kaplan-Meier analysis demonstrated survival of 99% (95% confidence interval [CI]: 97–100%) at 2 years and 98% (95% CI: 97–100%) at 8 years. Freedom from reoperation was 95.8% (95% CI: 91.2–100%) at 8 years. Freedom from endocarditis was 100% at 8 years. At the last echocardiographic follow-up, 95% of patients were free of severe aortic regurgitation (AR) and 82% free of moderate AR. Of the four patients who had severe AR, three underwent reoperations and received prosthetic valves and one is being clinically monitored.

Conclusion  This study reports early and midterm outcomes after VSARR-RT at our institution, including those patients who underwent a VSARR-RT procedure combined with other procedures. Further follow-up remains necessary to determine long-term outcomes.

Chronic opioid use after coronary bypass surgery

BACKGROUND

Opioid dependence has become a major health care issue. Pain management of invasive surgical procedures with opioids may potentially contribute to this epidemic. We sought to determine the association of opioid-prescribing patterns with chronic opioid use.

METHODS

We retrospectively reviewed all patients undergoing isolated coronary artery bypass graft (CABG) procedures during 2016 at a single institution. Prescribing patterns and medication usage were compared between opioid-naïve and opioid-exposed patients (patients with reported opioid use within 30 days prior to surgery). Chronic opioid dependence was defined as opioid usage beyond 90 days after discharge.

RESULTS

We included 284 opioid-naïve and 46 opioid-exposed patients. Although overall prescribing patterns were similar between groups, a higher proportion of opioid-exposed patients were prescribed a total dose >150 mg of oxycodone per discharge prescription (15.2% vs 4.9%; P = 0.024), and had a higher proportion of refills within 30 days (28.3% vs 10.9%; relative risk [RR] 3.2 [95% confidence interval (CI): 1.5-6.8]; all P < 0.05). The incidence of chronic opioid dependence was higher among opioid-exposed patients compared to opioid-naïve patients (21.7% vs 3.2%; RR 8.5 [95%CI: 3.2-22.3]; P = 0.001).

CONCLUSIONS

Ongoing opioid use 3 months after CABG is present in 21.7% of opioid-exposed patients and 3.2% of opioid-naïve patients. These preliminary findings highlight the burden of prescribing patterns on the overall opioid epidemic and the need to develop alternative pain management strategies.

Should the dilated ascending aorta be repaired at the time of bicuspid aortic valve replacement?

OBJECTIVES

Bicuspid aortic valve (BAV) is the most common congenital valvular abnormality and frequently presents with accelerated calcific aortic valve disease, requiring aortic valve replacement (AVR) and thoracic aortic aneurysm and dissection. Supporting evidence for Association Guidelines of aortic dimensions for aortic resection is sparse. We sought to determine whether concurrent repair of dilated or aneurysmal aortic disease during AVR in patients with BAV substantially improves morbidity and mortality outcomes.

METHODS

Mortality and reoperation outcomes of 1301 adults with BAV and dilated aorta undergoing AVR-only surgery were compared to patients undergoing AVR with aortic resection (AVR-AR) using Cox proportional hazards modelling and patient matching.

RESULTS

Clinically important differences in patient characteristics, aortic valve function and aortic dimensions were identified between cohorts. Event rates were low, with rates of reoperation and death within 1 year of only 1.8% and 5.4%, respectively, and no aortic dissection observed during follow-up. There were no significant differences in reoperation or mortality outcomes between the AVR-only and AVR-AR cohorts. Age, aortic dimension or a combination thereof was not associated with better or worse outcomes after each AVR-AR compared with AVR.

CONCLUSIONS

We conclude AVR-only and AVR-AR surgery have low morbidity and mortality and have utility over a wide range of age and aortic sizes. Our results do not provide support for the 45-mm aortic dimension recommended in the current guidelines for aortic resection while performing AVR or any other specific dimension.

Effectiveness and Safety of Transcatheter Aortic Valve Implantation for Aortic Stenosis in Patients With "Porcelain" Aorta

Surgical aortic valve replacement (SAVR) in patients with porcelain aorta is considered a high-risk procedure. Hence, transcatheter aortic valve implantation (TAVI) is emerging as the intervention of choice. However, there is a paucity of data directly comparing TAVI with SAVR in patients with porcelain aorta. We compared outcomes of TAVI versus SAVR in high-risk patients with porcelain between March 2012 and June 2015. The TAVI group included 54 patients, whereas 130 SAVR patients with porcelain aorta were identified (operated on between 2004 and 2015). Both groups were matched 1:1 based on the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score with a 0.5% a priori caliper, resulting in 52 matched pairs. The mean STS-PROM was 7.3 ± 3.9 for both groups (p = 0.98), whereas mean age was 77.5 years for TAVI and 78.8 years for SAVR (p = 0.46). Compared with SAVR, TAVI patients had lower operative mortality (3.8% vs 17.3%; p = 0.052), significantly shorter median intensive care unit (40 vs 107 hours; p < 0.001) and hospital (5 vs. 7 days; p < 0.001) length of stay (LOS), but similar postoperative stroke rates (7.7% vs 11.5%; p = 0.74). One-year unadjusted survival was 81.7% (95% confidence interval [CI]: 69.8% to 93.5%) in the TAVI group versus 71.2% (95% CI: 61.0% to 85.1%) in the SAVR group, p = 0.093. Cox proportional hazard modeling identified preoperative chronic kidney disease (hazard ratio: 2.63 [95% CI: 1.03 to 6.70]; p = 0.043) and SAVR (hazard ratio: 2.641 [95% CI: 1.07 to 6.51]; p = 0.035) as significant predictors for decreased survival. Overall, TAVI was associated with reduced operative mortality, increased survival, and shorter intensive care unit and hospital length of stay compared with SAVR in patients with porcelain aorta. This study demonstrates that TAVI is a safe intervention in this high-risk population.

The risk of reoperative cardiac surgery in radiation-induced valvular disease

OBJECTIVE

Mediastinal radiation therapy (MRT) increases the risk for adverse outcomes after cardiac surgery and is not incorporated in the Society of Thoracic Surgeons (STS) risk algorithm. We aimed to quantify the surgical risk conferred by MRT in patients undergoing primary and reoperative valvular operations.

METHODS

A retrospective analysis of 261 consecutive patients with prior MRT who underwent valvular operations between January 2002 and May 2015. Short- and long-term outcomes were compared for STS predicted risk of mortality, surgery type, gender, year of surgery, and age-matched patients stratified by reoperative status.

RESULTS

Mean age was 62.6 ± 12.1 years and 174 (67%) were women. The majority had received MRT for Hodgkin lymphoma (48.2%) and breast cancer (36%). Overall, 214 (82%) were primary and 47 (18%) were reoperative procedures. Reoperation carried a higher operative mortality than primary cases (17% vs 3.7%; P = .003). Compared with the 836 nonradiated matches, operative mortality and observed-to-expected STS mortality ratios were higher in primary (3.8% [1.4] vs 0.8% [0.32]; P = .004) and reoperative (17% [3.35] vs 2.3% [0.45]; P = .001) patients with prior MRT. Cox proportional hazard modeling revealed that in patients with previous MRT, primary (hazard ratio, 2.24; 95% confidence interval, 1.73-2.91) and reoperative status (hazard ratio, 3.19; 95% confidence interval, 1.95-5.21) adversely affected long-term survival compared with nonradiated matches.

CONCLUSIONS

Surgery for radiation-induced valvular heart disease has a higher operative mortality than predicted by STS predicted risk of mortality. Reoperations are associated with increased morbidity and mortality compared with primary cases. Careful patient selection is paramount and expanded indications for transcatheter therapies should be considered, especially in reoperative patients.

Risk and outcomes of aortic valve endocarditis among patients with bicuspid and tricuspid aortic valves

Objective

Patients with structural abnormalities of cardiac valves, including bicuspid aortic valve (BAV), are said to be at higher risk of infective endocarditis (IE). We sought to determine the risk of IE of the BAV compared with the tricuspid aortic valve (TAV) and to determine the risk of aortic valve replacement and mortality after IE.

Methods

From medical records of two US and one Italian hospitals, patients with their first episode of IE of any native valve were identified. In the US cohort 42 patients with BAV and 393 patients with TAV with IE occurring between 1 January 2000 and 30 June 2014 were identified. In the Italian cohort 48 patients with BAV and 341 patients with TAV with IE underwent valve replacement surgery between 1 January 2000 and1 November 2015. The risk of IE for BAV and TAV and subsequent outcomes were determined after matching to patients without IE.

Results

After adjustment for risk factors, the risk of IE in the US cohort was 23.1 (95% CI 8.1 to 100, p <0.0001) times greater for BAV than TAV. Patients with BAV with IE were more likely to have an aortic root abscess. Within the subsequent 5 years, BAV patients with IE were more likely to undergo valve replacement (85%) than TAV patients with IE (46%). Patients with IE were at increased risk of death. The findings were similar in the Italian cohort.

Conclusions

Patients with BAV are at markedly increased risk of IE and aortic root abscess than patients with TAV. Increased risk of IE in patients with BAV indicates they may be a candidate group for long-term trials of antibiotic prophylaxis of IE.

Post-operative atrial fibrillation examined using whole-genome RNA sequencing in human left atrial tissue

Background

Both ambulatory atrial fibrillation (AF) and post-operative AF (poAF) are associated with substantial morbidity and mortality. Analyzing the tissue-specific gene expression in the left atrium (LA) can identify novel genes associated with AF and further the understanding of the mechanism by which previously identified genetic variants associated with AF mediate their effects.

Methods

LA free wall samples were obtained intraoperatively immediately prior to mitral valve surgery in 62 Caucasian individuals. Gene expression was quantified on mRNA harvested from these samples using RNA sequencing. An expression quantitative trait loci (eQTL) analysis was performed, comparing gene expression between different genotypes of 1.0 million genetic markers, emphasizing genomic regions and genes associated with AF.

Results

Comparison of whole-genome expression between patients who later developed poAF and those who did not identified 23 differentially expressed genes. These included genes associated with the resting membrane potential modified by potassium currents, as well as genes within Wnt signaling and cyclic GMP metabolism. The eQTL analysis identified 16,139 cis eQTL relationships in the LA, including several involving genes and single nucleotide polymorphisms (SNPs) linked to AF. A previous relationship between rs3744029 and MYOZ1 expression was confirmed, and a novel relationship between rs6795970 and the expression of the SCN10A gene was identified.

Conclusions

The current study is the first analysis of the human LA expression landscape using high-throughput RNA sequencing. Several novel genes and variants likely involved in AF pathogenesis were identified, thus furthering the understanding of how variants associated with AF mediate their effects via altered gene expression.

Trial registration

ClinicalTrials.gov ID: NCT00833313, registered 5. January 2009

Electronic supplementary material

The online version of this article (doi:10.1186/s12920-017-0270-5) contains supplementary material, which is available to authorized users.

Vancomycin Paste Does Not Reduce the Incidence of Deep Sternal Wound Infection After Cardiac Operations

BACKGROUND

Deep sternal wound infection (DSWI) is a devastating complication that increases morbidity and death in cardiac surgical patients. Vancomycin is often administered intravenously for antibiotic prophylaxis in cardiac operations. Many cardiac surgeons also apply vancomycin paste topically to the sternal edges. We examined the effect of vancomycin paste on the incidence of DSWI in patients undergoing elective cardiac operations.

METHODS

We retrospectively reviewed the medical records of all patients from 2003 to 2015 who underwent coronary artery bypass grafting, valve, or combined coronary artery bypass grafting and valve operations at a single institution. We derived The Society for Thoracic Surgeons (STS) DSWI risk index for each patient and systematically reviewed operative, pharmacy, microbiology, and discharge records to document DSWI in these patients. Multivariate analyses were used to identify predictors of DSWI in this cohort and to quantify the effect of vancomycin paste.

RESULTS

Of the 14,492 patients whose records we examined, DSWI developed in 136 patients, resulting in an overall incidence of 0.9%. After multivariate analysis, body mass index, New York Heart Association Functional Classification, and the STS DSWI risk index remained statistically significant and associated with DSWI. Although the incidence of DSWI decreased over time, the use of vancomycin paste was not associated with a reduced incidence of DSWI.

CONCLUSIONS

There was a marked decrease in the incidence of DSWI during the study period, concurrent with institutional implementation of revised STS antibiotic dosing guidelines in 2007 and other strategies. However, the application of vancomycin paste to the sternal edges of patients undergoing cardiac operations was not associated with a reduced risk of DSWI.

Allele-specific expression in the human heart and its application to postoperative atrial fibrillation and myocardial ischemia

BACKGROUND

Allele-specific expression (ASE) is differential expression of each of the two chromosomal alleles of an autosomal gene. We assessed ASE patterns in the human left atrium (LA, n = 62) and paired samples from the left ventricle (LV, n = 76) before and after ischemia, and tested the utility of differential ASE to identify genes associated with postoperative atrial fibrillation (poAF) and myocardial ischemia.

METHODS

Following genotyping from whole blood and whole-genome sequencing of LA and LV samples, we called ASE using sequences overlapping heterozygous SNPs using rigorous quality control to minimize false ASE calling. ASE patterns were compared between cardiac chambers and with a validation cohort from cadaveric tissue. ASE patterns in the LA were compared between patients who had poAF and those who did not. Changes in ASE in the LV were compared between paired baseline and post-ischemia samples.

RESULTS

ASE was found for 3404 (5.1%) and 8642 (4.0%) of SNPs analyzed in the LA and LV, respectively. Out of 6157 SNPs with ASE analyzed in both chambers, 2078 had evidence of ASE in both LA and LV (p < 0.0001). The SNP with the greatest ASE difference in the LA of patients with and without postoperative atrial fibrillation was within the gelsolin (GSN) gene, previously associated with atrial fibrillation in mice. The genes with differential ASE in poAF were enriched for myocardial structure genes, indicating the importance of atrial remodeling in the pathophysiology of AF. The greatest change in ASE between paired post-ischemic and baseline samples of the LV was in the zinc finger and homeodomain protein 2 (ZHX2) gene, a modulator of plasma lipids. Genes with differential ASE in ischemia were enriched in the ubiquitin ligase complex pathway associated with the ischemia-reperfusion response.

CONCLUSIONS

Our results establish a pattern of ASE in the human heart, with a high degree of shared ASE between cardiac chambers as well as chamber-specific ASE. Furthermore, ASE analysis can be used to identify novel genes associated with (poAF) and myocardial ischemia.

Association between bicuspid aortic valve morphotype and regional dilatation of the aortic root and trunk

Thoracic aortic disease, including thoracic aortic aneurysm (TAA), is frequently seen in patients with bicuspid aortic valve (BAV). We hypothesized that BAV morphotype would be associated with aortic aneurysm phenotypes but that other patient variables would significantly modify this relationship. 829 patients between 18 and 90 years with BAV and available raw imaging of the aortic valve and the ascending aorta to its mid-portion prior to aortic valve and aortic surgery were examined. The sinuses of Valsalva and proximal ascending aorta were measured from 2-dimensional co-planar echocardiographic images. We observed strong associations between patient habitus and raw and normalized dimensions of the aortic root and ascending aorta. Patients with R-L morphotype presented at an older age with larger aortic root but similar ascending aortic dimensions. After accounting for patient morphometric characteristics and severity of aortic valve disease, patients with R-L valve morphotype were marginally more likely to have an aortic root aneurysm (86% vs. 78%; P = 0.043), defined as aortic root dimension Z score ≥3. We observed only small differences in aortic dimensions between BAV morphotypes, that are eclipsed by variation in patient habitus. We interpret these findings to mean that BAV patients will not likely benefit from therapies based on aortic valve morphotype. Rather, we propose that all BAV patients should undergo longitudinal follow-up, independent of valve morphotype. Guidelines for aortic surgery based upon dimensions alone may be improved by considering patient characteristics such as age, body size and other characteristics.

Duration of Postoperative Atrial Fibrillation After Cardiac Surgery Is Associated With Worsened Long-Term Survival

BACKGROUND

Studies of the effects of postoperative atrial fibrillation (poAF) on long-term survival are conflicting, likely because of comorbidities that occur with poAF and the patient populations studied. Furthermore, the effects of poAF duration on long-term survival are poorly understood.

METHODS

We utilized a prospectively collected database on outcomes of cardiac surgery at a large tertiary care institution between August 2001 and December 2010 with survival follow-up through June 2015 to analyze long-term survival of patients with poAF. In addition, we identified patient- and procedure-related variables associated with poAF, and estimated overall comorbidity burden using the Elixhauser comorbidity index. Survival was compared between patients with poAF (n = 513) and a propensity score matched control cohort, both for all patients and separately for subgroups of patients with poAF lasting less than 2 days (n = 218) and patients with prolonged poAF (n = 265).

RESULTS

Patients with poAF were older and had a higher burden of comorbidities. Survival was significantly worse for patients with poAF than for the matched control group (hazard ratio 1.43, 95% confidence interval: 1.11 to 1.86). That was driven by decreased survival among patients with prolonged poAF (hazard ratio 1.97, 95% confidence interval: 1.37 to 2.80), whereas survival of patients with poAF for less than 2 days was not significantly different from that of matched controls (hazard ratio 0.91, 95% confidence interval: 0.60 to 1.39).

CONCLUSIONS

After close matching based on comorbidity burden, prolonged poAF is still associated with decreased survival. Therefore, vigilance is warranted in monitoring and treating patients with prolonged poAF after cardiac surgery.

Point-of-care platelet function testing predicts bleeding in patients exposed to clopidogrel undergoing coronary artery bypass grafting: Verify pre-op TIMI 45--a pilot study

BACKGROUND

Guidelines recommend delaying coronary artery bypass grafting (CABG) for 5 days after discontinuing clopidogrel. However, platelet function may recover quicker in certain individuals.

HYPOTHESIS

We hypothesized that perioperative measurement of platelet function with a point-of-care P2Y12 inhibitor assay could predict bleeding during CABG in patients exposed to clopidogrel.

METHODS

Verify Pre-Op TIMI 45 was a prospective pilot study of 39 patients on clopidogrel who subsequently underwent CABG. Preoperative on-treatment platelet reactivity was assessed with VerifyNow P2Y12 Reaction Units (PRU), with higher PRU indicating more reactive platelets. Outcomes were stratified by PRU quartiles, as well as prespecified cutpoints for the lowest quartile (PRU 173), a cutpoint for major bleeding determined by the Youden index using receiver operator curve analysis (PRU 207), and clopidogrel resistance (PRU 230).

RESULTS

Patients in higher PRU quartiles experienced smaller decreases in hemoglobin and hematocrit (P < 0.05 for all comparisons), less major bleeding (P = 0.021), and less major or minor bleeding (P = 0.003). Patients above the PRU 207 and 230 cutpoints had less chest-tube output (P = 0.041 and P = 0.012, respectively), less major bleeding (P = 0.005 and P = 0.036, respectively), and less major or minor bleeding (P = 0.013 and P < 0.001, respectively). By receiver operator curve analysis, preoperative PRU ≤ 207 discriminated between patients with and without major bleeding during surgery (area under the curve: 0.76, 95% confidence interval: 0.59-0.94, P = 0.018).

CONCLUSIONS

In this pilot study, we found that point-of-care platelet function assessment could predict bleeding in patients recently exposed to clopidogrel undergoing CABG.

Discharge outcomes in patients with paracorporeal biventricular assist devices

BACKGROUND

As waiting time for heart transplantation has increased, ventricular assist devices have become critical for "bridging" patients with end-stage heart failure. Because most reported post-discharge experience is with left ventricular assist devices (LVAD), we sought to evaluate the safety and feasibility of home discharge on paracorporeal biventricular assist devices (BIVAD).

METHODS

We retrospectively reviewed the hospital course and post-discharge outcomes of 46 consecutive patients who received paracorporeal VADs as bridge to transplant. The success of home discharge was assessed by frequency and reasons for hospital readmission and survival to transplant.

RESULTS

Thirty patients (65%) were successfully transferred from the intensive care unit and considered candidates for discharge. Of the 26 patients discharged home, 11 were supported with an LVAD and 15 with BIVADs. Median duration of support until transplant, explant, or death did not differ significantly between LVAD or BIVAD patients (91 days vs 158 days; p = 0.09). There were 26 readmissions for medical or device-related complications; 10 in 7 LVAD patients and 16 in 10 BIVAD patients, with no difference in median length of stay (17 days vs 25 days; p = 0.67). Out of hospital duration of support was similar between LVAD and BIVAD patients (61 days vs 66 days; p = 0.87) as were 6-month and 1-year event-free survival rates (p = 0.49).

CONCLUSIONS

Outcomes were similar in patients bridged to transplant on home paracorporeal BIVAD versus LVAD support. We recommend discharge for stable patients demonstrating device competency and adequate home care regardless of the need for univentricular or biventricular paracorporeal support.

Heparin concentration-based anticoagulation for cardiac surgery fails to reliably predict heparin bolus dose requirements

BACKGROUND

Hemostasis management has evolved to include sophisticated point-of-care systems that provide individualized dosing through heparin concentration-based anticoagulation. The Hepcon HMS Plus system (Medtronic, Minneapolis, MN) estimates heparin dose, activated clotting time (ACT), and heparin dose response (HDR). However, the accuracy of this test has not been systematically evaluated in large cohorts.

METHODS

We examined institutional databases for all patients who underwent cardiac surgery with cardiopulmonary bypass (CPB) at our institution from February 2005 to July 2008. During this period, the Hepcon HMS Plus was used exclusively for assessment of heparin dosing and coagulation monitoring. Detailed demographic, surgical, laboratory, and heparin dosing data were recorded. ACT, calculated and measured HDR, and heparin concentrations were recorded. Performance of the Hepcon HMS Plus was assessed by comparison of actual and target ACT values and calculated and measured HDR.

RESULTS

In 3880 patients undergoing cardiac surgery, heparin bolus dosing to a target ACT resulted in wide variation in the postheparin ACT (r(2) = 0.03). The postheparin ACT did not reach the target ACT threshold in 7.4%(i.e., when target ACT was 300 s) and 16.9% (i.e., when target ACT was 350 s) of patients. Similarly, the target heparin level calculated from the HDR did not correlate with the postbolus heparin level, with 18.5% of samples differing by more than 2 levels of the assay. Calculated and measured HDR were not linearly related at any heparin level.

CONCLUSIONS

The Hepcon HMS Plus system poorly estimates heparin bolus requirements in the pre-CPB period. Further prospective studies are needed to elucidate what constitutes adequate anticoagulation for CPB and how clinicians can reliably and practically assess anticoagulation in the operating room.