A Systematic Review of Mortality Associations in Patients who Develop Tracheoinnominate Artery Fistula Following Tracheostomy

OBJECTIVE

Tracheoinnominate artery fistulas (TIFs) are a rare but deadly complication of tracheostomy. Tracheoinnominate artery fistula cases in the literature were summarized in order to understand mortality associations.

METHODS

MEDLINE was searched for studies reporting individual characteristics of patients with TIFs after tracheostomy, excluding cases without tracheostomy or with additional procedures at the tracheostomy site. This study followed PRISMA guidelines.

RESULTS

121 TIF patients from 18 case series and 46 case reports were included. The median age was 40 years, and 52.9% were male. The overall mortality rate was 64.5%. There were differences in mortality between cases that presented initially with vs without sentinel bleeding (odds ratio [OR] .34; CI [confidence interval] .16-.73; P = .006). The mortality rate also differed in whether or not the tracheostomy cuff was over-inflated for temporary hemostasis during resuscitation (OR 3.57 (CI 1.57-8.09); P = .002). Treatment compared to no treatment had lower mortality rates (OR .11 (CI 0.04-.32); P < .001); no differences were found if treatment was endovascular vs open surgical.

CONCLUSIONS

Mortality is a major concern after detection of a TIF and resuscitation paired with endovascular or open surgical intervention is imperative. Rapidly investigating sentinel bleeds and intervening upon hemorrhage with temporary cuff over inflation may lead to improved outcomes.

Acute-on-Chronic Aortic Dissection: Management and Outcomes of the Unstable "Triple-Lumen" Aorta

BACKGROUND

The impact of acute aortic dissection of the chronically dissected distal aorta is unknown. This study sought to describe the incidence and characteristics of the triple-lumen aortic dissection and its impact on survival.

METHODS

From 2010 to 2021, a query of a single-institution aortic database identified 1149 patients with chronic distal aortic dissection. Thirty-three (2.9%) patients with at least 3 distinct lumens and 2 separate "primary" intimal tears were identified by analysis of contrast-enhanced cross-sectional imaging. Triple-lumen patients were exactly matched with a cohort of double-lumen patients on a 1:1 ratio using 5 preoperative variables, and outcomes between the groups were assessed.

RESULTS

The median age at time of initial dissection in patients with a triple-lumen dissection was 46 years. Initial dissection was a type A in 33% and a type B in 67% of patients. The median time from initial dissection to triple-lumen diagnosis was 4.2 years. On diagnosis of the triple-lumen aorta, 85% of patients required urgent aortic repair for rapid growth (36%), aortic diameter ≥55 mm (30%), malperfusion (6%), intractable pain (6%), and rupture/type A (6%). Thirty-day mortality after triple lumen dissection was 12%.

CONCLUSIONS

Acute-on-chronic distal dissection resulting in a triple-lumen aorta should be classified as a "complicated" type B dissection as these patients typically have large aneurysms and a high incidence of rapid false lumen expansion requiring urgent surgical repair.

Renal Dysfunction at Discharge and Long-Term Survival in Acute Type A Aortic Dissection

INTRODUCTION

We aimed to investigate the association between renal dysfunction at discharge and long-term survival in acute type A aortic dissection (ATAAD) patients following surgery.

METHODS

From 2000 to 2021, 784 patients underwent aortic repair for an ATAAD. Patients were stratified based on creatinine (Cr) level at discharge alive or dead: normal Cr (n = 582) and elevated Cr defined as >1.3 mg/dL for males and >1.0 mg/dL for females or on dialysis at discharge (n = 202).

RESULTS

Preoperatively, both groups had similar rates of comorbidities except for the elevated-Cr group which had more diabetes, chronic obstructive pulmonary disease, and chronic and acute renal insufficiency. Both groups had similar open ATAAD repair procedures. Postoperative outcomes in the elevated-Cr group were significantly worse, including six times higher operative mortality (20% versus 3.4%, P < 0.0001). The landmark long-term survival after discharge alive was significantly worse in the elevated-Cr group than the normal-Cr group (10-y survival: 48% versus 69%, P = 0.0009). The elevated Cr on dialysis at discharge group had significantly worse five-year survival (40%) than the elevated Cr not on dialysis at discharge group (80%, P = 0.02) and the normal-Cr group (87%, P < 0.0001). Additionally, the elevated Cr not on dialysis had a worse five-year survival than the normal-Cr group (80% versus 87%, P = 0.02). Elevated Cr at discharge on dialysis was a significant risk factor for late mortality (hazard ratio = 4.22, 95% confidence interval: [2.07, 8.61], P < 0.0001).

CONCLUSIONS

Renal dysfunction at discharge was associated with significantly decreased short-term and long-term survival following open ATAAD repair. Surgeons should aggressively prevent renal dysfunction, especially new-onset dialysis, at discharge as it is correlated with significantly worse short-term and long-term outcomes.

Redo aortic surgery: Does one versus multiple affect outcomes?

Objective

Redo aortic surgery has a higher risk of morbidity and mortality because it is technically complex due to mediastinal adhesions, infection, and previously implanted prostheses. In this study, we sought to benchmark our single-center experience comparing outcomes in patients undergoing aortic surgery after 1 versus multiple previous cardiac operations.

Methods

Between 2004 and 2019, 429 patients underwent redo aortic surgery. They were classified as aortic surgery after 1 previous surgery (first redo surgery, n = 360) and aortic surgery after 2 or more (multiple) previous surgeries (multiple redo surgery, n = 69). Postoperative outcomes and long-term survival were compared, and risk factors for mortality were identified.

Results

Thirty-day mortality was lower in first redo surgery compared with multiple redo surgery (12.3% vs 21.7%, P = .03). Age, cardiopulmonary bypass time, intra-aortic balloon pump use, postoperative cerebrovascular accident, absence of postoperative atrial fibrillation, intra-aortic balloon pump, and multiple redo surgery were independent predictors of 30-day mortality. Long-term survival was similar at 15 years. Patients who received first redo surgery were older (57.9 ± 14.0 years vs 50.3 ± 15.8 years, P = .0001) and had a higher incidence of hypertension (84.7% vs 73.9%, P = .02), whereas patients who received multiple redo surgery had a higher incidence of cerebrovascular disease (31.9% vs 20.3%, P = .03). Aortic valve replacement was the most common previous operation with higher incidence in multiple redo surgery. Incidence of previous aortic surgery was similar. Cardiopulmonary bypass (246 ± 67.3 minutes vs 219.9 ± 57.5 minutes, P = .009) and crossclamp times (208.2 ± 51.8 vs 181.9 ± 50.8 minutes, P = .004) were longer in multiple redo surgery. Incidence of reentry injury and balloon pump insertion were similar. Extracorporeal membrane oxygenation use was higher in multiple redo surgery. Postoperative complications occurred at similar rates, except for higher incidence of dialysis in multiple redo surgery (14.5% vs 7.2%, P = .04).

Conclusions

Multiple redo aortic procedures have a higher morbidity and mortality compared with first redo aortic procedures, with linearly increasing short-term mortality risk but similar long-term survival with the number of redo procedures.

Academic Rank and Productivity Among United States Cardiothoracic Surgeons

BACKGROUND

Despite a significant growth of women trainees in cardiothoracic surgery recently, women remain a minority of cardiothoracic surgeons and hold a minority of leadership positions. This study evaluates differences in cardiothoracic surgeon subspecialty choices, academic rank, and academic productivity between men and women.

METHODS

The Accreditation Council for Graduate Medical Education database was used to identify 78 cardiothoracic surgery academic programs in the United States, including integrated, 4+3, and traditional fellowships, as of June 2020. A total of 1179 faculty members were identified within these programs, 585 adult cardiac surgeons (50%), 386 thoracic surgeons (33%), and 168 congenital surgeons (14%), and other, 40 (3%). Data were collected using institutional websites, ctsnet.org, doximity.com, linkedin.com, and Scopus.

RESULTS

Of the 1179 surgeons, only 9.6% were women. Overall, women composed 6.7% of adult cardiac, 15% of thoracic, and 7.7% of congenital surgeons. Among subspecialties, women represent 4.5% (17 of 376) of full professors and 5% (11 of 195) of division chiefs in cardiothoracic surgery in the United States, have shorter career durations, and lower h-indices compared with men. However, women had similar m-indices, which factors in career length, compared with men in adult cardiac (0.63 vs 0.73), thoracic (0.77 vs 0.90), and congenital (0.67 vs 0.78) surgeons.

CONCLUSIONS

Career duration, including cumulative research productivity, appears to be the most important factors predicting full professor rank, potentially contributing to persistent sex-based disparities in academic cardiothoracic surgery.

Sex-specific disparities in patients undergoing isolated CABG

Study objective

Examine sex-specific characteristics in patients undergoing coronary artery bypass grafting (CABG) at our institution.

Design

Retrospective chart review was performed utilizing our institutional Society of Thoracic Surgeons (STS) database.

Setting

An academic, quaternary care center from 2010 to 2021.

Participants

3163 females and 9573 males underwent isolated CABG.

Interventions

The institutional STS database was queried for preoperative, intraoperative, and postoperative variables.

Main outcome measures

Univariate comparisons between female and male groups were performed using chi-squared tests or fisher exact tests. Multivariate logistic regression was used to assess risk factors for 30-day mortality.

Results

Females had more preoperative comorbidities than males, including hypertension, diabetes, peripheral arterial disease, cerebrovascular disease, renal failure, and prior myocardial infarction. Females more frequently underwent urgent (61 % vs. 58 %) or emergent CABG (5.8 % vs. 4.3 %) compared to males (p < 0.0001). Females experienced longer total intensive care unit (ICU) hours (48.3 h vs. 43.5 h) (p < 0.0001), were more frequently discharged to an extended care facility (13 % vs. 6.4 %) (p < 0.0001) and prescribed less aspirin and beta blocker therapy at discharge than males. In-hospital mortality was higher in females (1.9 % vs. 1.2 %, p = 0.002), as was 30-day mortality (2.7 % vs. 1.6 %, p = 0.0001). Female sex was an independent risk factor for 30-day mortality (odds ratio = 1.46, 95 % CI: 1.06, 2.03, p = 0.02).

Conclusion

Over the past decade, females undergoing CABG had more preoperative comorbidities, urgent and emergent operations, longer postoperative ICU stay and a higher risk of mortality than their male counterparts. Further studies must investigate these disparities to improve outcomes for females undergoing CABG.

Bentall versus valve-sparing aortic root replacement for root pathology with moderate-to-severe aortic insufficiency: a propensity-matched analysis

OBJECTIVES

To examine short- and long-term outcomes of patients with moderate-to-severe aortic insufficiency (AI) undergoing either a Bentall aortic root replacement (ARR) or valve-sparing root replacement (VSRR).

METHODS

A two-centre retrospective database of patients undergoing ARR from 2004 to 2021 was reviewed. Patients <18 years old were excluded. A total of 1527 adult patients underwent Bentall ARR (n = 1150, 75%) or VSRR (n = 377, 25%). Propensity score matching based on preoperative comorbidities was used and 195 matched pairs were identified. Perioperative outcomes, reoperation rates, recurrence of AI and long-term survival were evaluated.

RESULTS

ARR patients had more concomitant ascending aortic replacement (35% vs 20%, P = 0.002) and shorter cardiopulmonary bypass (189 vs 233 min, P < 0.0001) and aortic cross-clamp (170 vs 204 min, P < 0.0001) times than the VSRR group. Postoperatively, outcomes were similar between groups, including stroke (3% vs 2%) and in-hospital mortality (1.5% vs 2.1%), all P > 0.05. Indications for and rates of reoperation (4% vs 5%, P = 0.62) of the aortic valve and proximal aorta were similar between ARR and VSRR groups with reoperations occurring a mean of 3.2 years after initial root replacement. The ARR group had less moderate-to-severe AI than the VSRR group (1.6% vs 14%, P = 0.002) a mean of 3 years after surgery. Ten-year survival was similar between ARR (84%) and VSRR (82%) (P = 0.69) groups.

CONCLUSIONS

Both ARR and VSRR can be performed with acceptable short- and long-term outcomes in patients with moderate-to-severe AI.

Trends in surgical aortic valve replacement in pre- and post-transcatheter aortic valve replacement eras at a structural heart center

Background

The advent of transcatheter aortic valve replacement (TAVR) has directly impacted the lifelong management of patients with aortic valve disease. The U.S. Food and Drug Administration has approved TAVR for all surgical risk: prohibitive (2011), high (2012), intermediate (2016), and low (2019). Since then, TAVR volumes are increasing and surgical aortic valve replacements (SAVR) are decreasing. This study sought to evaluate trends in isolated SAVR in the pre- and post-TAVR eras.

Methods

From January 2000 to June 2020, 3,861 isolated SAVRs were performed at a single academic quaternary care institution which participated in the early trials of TAVR beginning in 2007. A formal structural heart center was established in 2012 when TAVR became commercially available. Patients were divided into the pre-TAVR era (2000-2011, n = 2,426) and post-TAVR era (2012-2020, n = 1,435). Data from the institutional Society of Thoracic Surgeons National Database was analyzed.

Results

The median age was 66 years, similar between groups. The post-TAVR group had a statistically higher rate of diabetes, hypertension, dyslipidemia, heart failure, more reoperative SAVR, and lower STS Predicted Risk of Mortality (PROM) (2.0% vs. 2.5%, p < 0.0001). There were more urgent/emergent/salvage SAVRs (38% vs. 24%) and fewer elective SAVRs (63% vs. 76%), (p < 0.0001) in the post-TAVR group. More bioprosthetic valves were implanted in the post-TAVR group (85% vs. 74%, p < 0.0001). Larger aortic valves were implanted (25 vs. 23 mm, p < 0.0001) and more annular enlargements were performed (5.9% vs. 1.6%, p < 0.0001) in the post-TAVR era. Postoperatively, the post-TAVR group had less blood product transfusion (49% vs. 58%, p < 0.0001), renal failure (1.4% vs. 4.3%, p < 0.0001), pneumonia (2.3% vs. 3.8%, p = 0.01), shorter lengths of stay, and lower in-hospital mortality (1.5% vs. 3.3%, p = 0.0007).

Conclusion

The approval of TAVR changed the landscape of aortic valve disease management. At a quaternary academic cardiac surgery center with a well-established structural heart program, patients undergoing isolated SAVR in the post-TAVR era had lower STS PROM, more implantation of bioprosthetic valves, utilization of larger valves, annular enlargement, and lower in-hospital mortality. Isolated SAVR continues to be performed in the TAVR era with excellent outcomes. SAVR remains an essential tool in the lifetime management of aortic valve disease.

Differences among sexes in presentation and outcomes in acute type A aortic dissection repair

OBJECTIVE

Female sex is a known risk factor in most cardiac surgery, including coronary and valve surgery, but unknown in acute type A aortic dissection repair.

METHODS

From 1996 to 2018, 650 patients underwent acute type A aortic dissection repair; 206 (32%) were female, and 444 (68%) were male. Data were collected through the Cardiac Surgery Data Warehouse, medical record review, and National Death Index database.

RESULTS

Compared with men, women were significantly older (65 vs 57 years, P < .0001). The proportion of women and men inverted with increasing age, with 23% of patients aged less than 50 years and 65% of patients aged 80 years or older being female. Women had significantly less chronic renal failure (2.0% vs 5.4%, P = .04), acute myocardial infarction (1.0% vs 3.8%, P = .04), and severe aortic insufficiency. Women underwent significantly fewer aortic root replacements with similar aortic arch procedures, shorter cardiopulmonary bypass times (211 vs 229 minutes, P = .0001), and aortic crossclamp times (132 vs 164 minutes, P < .0001), but required more intraoperative blood transfusion (4 vs 3 units) compared with men. Women had significantly lower operative mortality (4.9% vs 9.5%, P = .04), especially in those aged more than 70 years (4.4% vs 16%, P = .02). The significant risk factors for operative mortality were male sex (odds ratio, 2.2), chronic renal failure (odds ratio, 3.4), and cardiogenic shock (odds ratio, 6.8). The 10-year survival was similar between sexes.

CONCLUSIONS

Physicians and women should be cognizant of the risk of acute type A aortic dissection later in life in women. Surgeons should strongly consider operations for acute type A aortic dissection in women, especially in patients aged 70 years or more.

Surgical and endovascular repair for type B aortic dissections with mesenteric malperfusion syndrome: A systematic review of in-hospital mortality

OBJECTIVES

Mesenteric malperfusion is a feared complication of aortic dissection, with high mortality. The purpose of this study was to systematically review in-hospital mortality (IHM) of endovascular and surgical management of acute and chronic Stanford type B aortic dissections (TBAD) complicated by mesenteric malperfusion (MesMP).

METHODS

A systematic search of English language articles was conducted in relevant databases. Data on patient demographics, procedure details, and survival outcomes were collected. Reports were classified by type of intervention performed. Studies that failed to report patient-level outcomes based on specific intervention performed or IHM were excluded. Retrospective chart review of previously published data from a single institution was also performed to further identify cases of TBAD that were managed endovascularly. The Fisher exact test was performed to determine statistical significance.

RESULTS

In total, 37 articles were suitable for inclusion in this systematic review, which yielded 149 patients with a median age 55.0 years (interquartile range, 46.5-65 years) and 79% being male. Overall, in-hospital mortality was 12.8% (19/149) and was similar between endovascular and open surgical interventions (13% vs 11%, P = .99). Among endovascular strategies, IHM was greater, although not statistically significant in the thoracic endovascular aortic repair group compared with the fenestration/stenting without thoracic endovascular aortic repair group (24% vs 11%, P = .15).

CONCLUSIONS

Multiple strategies exist for the management of TBAD with MesMP; however, a majority of cases were managed endovascularly. Despite advances in therapies, mortality remains high at 13%.

Hypothermic circulatory arrest versus aortic clamping in thoracic and thoracoabdominal aortic aneurysm repair

BACKGROUND

To compare perioperative and midterm outcomes in thoracic and thoraco-abdominal aortic aneurysm (TAA and TAAA) repair using hypothermic circulatory arrest (HCA) or aortic clamping (AC) with mild hypothermia.

METHODS

From 2012 to 2021 there were 180 open repairs of a TAA or TAAA, of which 90 (50%) were done with HCA and 90 (50%) with aortic clamping with mild hypothermia. The indications for HCA were arch aneurysm, TAA from chronic aortic dissection, and inability to clamp the aorta for proximal anastomosis.

RESULTS

Compared to AC, the HCA group had less prior descending aorta replacement/repair (9.1% vs. 32%, p = 0.0001). Intraoperatively, the HCA group had more TAAs (70% vs. 20%, p < 0.0001) while the AC group had more TAAAs (80% vs. 30%, p < 0.0001). HCA group had longer cardiopulmonary bypass times (242 vs. 181 min, p < 0.0001) but shorter cross-clamp time (39 vs. 120 min, p < 0.0001) and lower temperatures (18°C vs. 34°C, p < 0.0001). Postoperatively, the HCA group had longer intubation times (31 vs. 26 h, p = 0.002), but all other postoperative outcomes including paralysis (2.2% vs. 8.9%, p = 0.08), and operative mortality (4.4% vs. 2.2%, p = 0.68) were similar between HCA and AC groups. Patient age was an independent risk factor for postoperative paralysis (OR 1.07, p = 0.03) while HCA was not significant (OR 0.37, p = 0.21). Five-year survival was similar between HCA and AC groups (85% vs. 80%, p = 0.36).

CONCLUSIONS

Postoperative outcomes and midterm survival were acceptable in thoracic and thoracoabdominal aneurysm patients after HCA or AC. Both HCA and AC with mild hypothermia were valid approaches in TAA/A repair.

Autologous blood transfusion in acute type A aortic dissection decreased blood product consumption and improved postoperative outcomes

Objective

To evaluate the effect of autologous blood use on blood product consumption and outcomes after acute type A aortic dissection repair.

Methods

From 2010 to October 2020, 497 patients underwent open acute type A aortic dissection repair, including those with autologous blood harvesting before cardiopulmonary bypass and transfusion after cardiopulmonary bypass (autologous blood transfusion [ABT], n = 397) and without autologous blood harvesting and transfusion (No-ABT, n = 100). The median ABT volume was 900 mL. Using propensity score matching, 89 matched pairs were identified based on age, sex, body mass index, preoperative hemoglobin, acute preoperative stroke, previous cardiac surgery, and cardiogenic shock.

Results

After propensity score matching, both groups were similar in demographic characteristics and aortic procedures. The ABT group required significantly less intraoperative transfusion of blood products (6 vs 11 units; P < .0001), including packed red blood cells (2 vs 4), fresh frozen plasma (2 vs 4), platelets (2 vs 2), and cryoprecipitate (0 vs 1); and combined intraoperative and postoperative transfusion (9 vs 13; P < .001). ABT was protective against intra- and postoperative blood product transfusion (odds ratio, 0.28; P = .01). The ABT group had significantly less sepsis, acute renal failure requiring dialysis, reintubation, and shorter intubation times and postoperative lengths of stay. Operative mortality was 6.7% in the ABT group versus 13% in the No-ABT group (P = .14). The midterm survival was similar between the 2 groups (5 year: 76% vs 74%). ABT had a hazard ratio of 0.81 for midterm mortality (P = .41).

Conclusions

Autologous blood transfusion was associated with better short-term outcomes and could be used routinely for acute type A aortic dissection repair. External multicenter prospective validation would be warranted.

Specialization in Acute Type A Aortic Dissection Repair: The Outcomes and Challenges

With increasing specialization within the field of cardiac surgery and a positive relationship between case volume and surgical outcomes in many areas, the concept of dedicated aortic surgeons performing acute type A aortic dissection (ATAAD) repair was investigated. From 1996 to 2014, 436 patients underwent open surgical repair of an ATAAD and were subsequently divided based on surgeon subspecialization, aortic-surgeon (AS, n = 401) vs non-aortic-surgeon (NAS, n = 35). Each aortic surgeon performed an average of 13 ATAAD repair operations per year. Preoperative comorbidities were similar between groups. Intraoperatively, the AS group had 36% aortic root replacement vs 23% in the NAS group, P = 0.12, and 36% zone 1/2/3 arch replacement vs 26% in the NAS group, P = 0.20). Postoperatively, the AS group had significantly better outcomes, including intraoperative mortality (1.2% vs 5.7%), 30-day mortality (6.5% vs 17%), and composite outcomes (23% vs 46%). Multivariable logistic regression showed NAS was a risk factor for 30-day mortality with an odds ratio (OR) of 4.4 (P = 0.03), as were COPD (OR = 4.0, P = 0.046) and cardiogenic shock (OR = 13.4, P < 0.0001). The 10-year survival was 66% in the AS group vs 46% in the NAS group, P = 0.02. NAS (HR = 2.2), Age (hazard ratio (HR) = 1.05), COPD (HR = 1.96), acute stroke (HR = 3.0), and New York Heart Association class III or IV (HR = 1.75) were significant risk factors for long-term mortality. Managing ATAAD by subspecialized aortic surgeons resulted in improved short- and long-term outcomes. Our specialty could consider ATAAD repair by high-volume aortic surgeons for better patient outcomes.

Aortic and Arch Branch Vessel Cannulation in Acute Type A Aortic Dissection Repair

Objective

To evaluate central aortic cannulation and arch branch vessel (ABV) cannulation in acute type A aortic dissection repair.

Methods

From 2015 to April 2020, 298 patients underwent open repair of an acute type A aortic dissection. Patients undergoing femoral cannulation for cardiopulmonary bypass (n = 34) were excluded. Patients were then divided based on initial cannulation for cardiopulmonary bypass into central aortic cannulation (n = 72) and ABV cannulation (n = 192) groups. ABV sites included cannulation of the axillary, innominate, right/left common carotid, and intrathoracic right subclavian arteries.

Results

The aortic cannulation group was younger (59 vs 62 years; P = .02), more likely to be men (76% vs 60%; P = .02), and had more peripheral vascular disease (60% vs 37%; P = .0009). ABV dissection was similar between central and ABV cannulation groups (53% vs 60%; P = .51). The aortic cannulation group underwent less aggressive arch replacement, had shorter cardiopulmonary bypass times (200 vs 222 minutes; P = .01), less utilization of antegrade cerebral perfusion (93% vs 98%; P = .04), and received less blood transfusion (0 vs 1 U; P = .001). Postoperative outcomes were similar between aortic and ABV cannulation groups, including stroke (5.6% vs 5.2%; P = 1.0) and operative mortality (4.2% vs 6.3%; P = .77). In addition, postoperative strokes were similar in location (right-brain, left-brain, or bilateral), etiology (embolic vs hemorrhagic), and presence of permanent deficits. Aortic cannulation was not a risk factor for postoperative stroke (odds ratio, 0.94; P = .91) or operative mortality (odds ratio, 0.70; P = .64). Short-term survival was similar between central and ABV cannulation groups.

Conclusions

Both aortic and ABV cannulation were safe and effective cannulation strategies in acute type A aortic dissection repair.

Perioperative Outcomes of Acute Type-A Aortic Dissection Repair was Unaffected by COVID-19 Testing Delay

Background:

This study assesses impact of COVID-19 testing delay on perioperative outcomes of Acute Type A Aortic Dissection (ATAAD) repair at a single institution.

Methods:

From January 2010 – May 2021, 539 ATAAD patients underwent open aortic repair at our institution. Sixty-five of these patients had open aortic repair during COVID (March 2020 – May 2021) and 474 patients were pre-COVID (January 2010 – February 2020).

Results:

Compared to the pre-COVID group, patients During-COVID had a higher proportion of previous myocardial ischemia [9/65 (14%) vs 28/474 (5.9%), p=0.03], chronic obstructive pulmonary disease [14/65 (22%) vs 55/474 (12%), p=0.02], and renal malperfusion syndrome [11/65 (17%) vs 30/474 (6.4%), p=0.01]. There was no significant difference in surgical outcomes between groups, including operative mortality (7.6% vs 9.2%, p=0.64). The median admission-to-Operating Room (OR) time was 107 minutes in the During-COVID group compared to 87 minutes in pre-COVID group, p=0.88. During COVID, the median admission-to-OR time was significantly longer in the Waiting group compared to the No-waiting group (209 min vs 75min, p=0.0009). Only one patient had positive COVID test. There were no aortic ruptures while awaiting COVID testing results. There was a total of 6 reported deaths in the During-COVID group: 1 patient died post-surgery due to ARDS caused by COVID, and others due to ischemic stroke (3 patients) and organ failure (2 patients).

Conclusions:

Perioperative outcomes of ATAAD patients were similar during-COVID compared to pre-COVID. Waiting for COVID testing results did not significantly affect the perioperative outcomes among ATAAD patients after repair.

Cardiorespiratory Fitness After Open Repair for Acute Type A Aortic Dissection - A Prospective Study

Cardiorespiratory fitness (as measured by peak oxygen consumption [VO2peak]) is an independent predictor of cardiovascular disease and all-cause mortality. Limited data exist on VO2peak following repair for an acute type A aortic dissection (ATAAD) or proximal thoracic aortic aneurysm (pTAA). This study prospectively evaluated VO2peak, functional capacity, and health-related quality of life (HR-QOL) following open repair. Participants with a history of an ATAAD (n = 21) or pTAA (n = 43) performed cardiopulmonary exercise testing (CPX), 6-minute walk testing, and HR-QOL at 3 (early) and 15 (late) months following open repair. The median age at time of surgery was 55-years-old and 60-years-old in the ATAAD and pTAA groups, respectively. Body mass index significantly increased between early and late timepoints for both ATAAD (p = 0.0245, 56% obese) and pTAA groups (p = 0.0045, 54% obese). VO2peak modestly increased by 0.8 mLO2·kg-1·min-1 within the ATAAD group (p = 0.2312) while VO2peak significantly increased by 2.2 mLO2·kg-1·min-1 within the pTAA group (p = 0.0003). Anxiety significantly decreased in the ATAAD group whereas functional capacity and HR-QOL metrics (social roles and activities, physical function) significantly improved in the pTAA group (p values < 0.05). There were no serious adverse events during CPX. Cardiorespiratory fitness among the ATAAD group remained 36% below predicted normative values >1 year after repair. CPX should be considered post-operatively to evaluate exercise tolerance and blood pressure response to determine whether mild-to-moderate aerobic exercise should be recommended to reduce future risk of morbidity and mortality.

Is hemiarch replacement adequate in acute type A aortic dissection repair in patients with arch branch vessel dissection without cerebral malperfusion?

OBJECTIVE

The study objective was to determine if hemiarch replacement is an adequate arch management strategy for patients with acute type A aortic dissection and arch branch vessel dissection but no cerebral malperfusion.

METHODS

From January 2008 to August 2019, 479 patients underwent open acute type A aortic dissection repair. After excluding those with aggressive arch replacement (n = 168), cerebral malperfusion syndrome (n = 34), and indeterminable arch branch vessel dissection (n = 1), 276 patients with an acute type A aortic dissection without cerebral malperfusion syndrome who underwent hemiarch replacement comprised this study. Patients were then divided into those with arch branch vessel dissection (n = 133) and those with no arch branch vessel dissection (n = 143).

RESULTS

The median age of the entire cohort was 62 years, with the arch branch vessel dissection group being younger (60 vs 62 years, P = .048). Both groups had similar aortic arch and descending thoracic aortic diameters, with significantly more DeBakey type I dissections (100% vs 80%) in the arch branch vessel dissection group. The arch branch vessel dissection group had more aortic root replacement (36% vs 27%, P = .0035) and longer aortic crossclamp times (153 vs 128 minutes, P = .007). Postoperative outcomes were similar between the arch branch vessel dissection and no arch branch vessel dissection groups, including stroke (10% vs 5%, P = .12) and operative morality (7% vs 5%, P = .51). The arch branch vessel dissection group had a significantly greater cumulative incidence of reoperation (8-year: 19% vs 4%, P = .04) with a hazard ratio of 2.89 (95% confidence interval, 1.01-8.27; P = .048), which was similar between groups among only DeBakey type I dissections (8-year: 19% vs 5%, P = .11). The 8-year survival was similar between the arch branch vessel dissection and no arch branch vessel dissection groups (76% vs 74%, P = .30).

CONCLUSIONS

Hemiarch replacement was adequate for patients with acute type A aortic dissection with arch branch vessel dissection without cerebral malperfusion syndrome, but carried a higher risk of late reoperation.

Managing Malperfusion Syndrome in Acute Type A Aortic Dissection With Previous Cardiac Surgery

BACKGROUND

Patients with acute type A aortic dissection with a previous cardiac surgery (PCS) and malperfusion syndrome (MPS) are extremely difficult to manage and have poor outcomes.

METHODS

From 1996 to 2018, 668 patients underwent emergent open aortic repair or endovascular fenestration/stenting for MPS for an acute type A aortic dissection, including those with PCS (PCS, n = 64) and those without PCS (No-PCS, n = 604). The groups were further divided into PCS+MPS, PCS+No-MPS, No-PCS+MPS, and No-PCS+No-MPS.

RESULTS

Compared with the No-PCS group, the PCS group had significantly more coronary artery disease, acute renal failure, and mesenteric and renal MPS. Forty-two percent of patients with PCS underwent upfront endovascular fenestration/stenting for endovascular-amendable MPS. The in-hospital mortality was significantly higher in patients with PCS+MPS (40%) compared with PCS+No-MPS (5.9%), No-PCS+MPS (30%), and No-PCS+No-MPS (6.7%). Multivariable logistic regression showed cardiogenic shock (odds ratio, 7.3) and MPS (odds ratio, 6.6) were risk factors for in-hospital mortality (P < .001). After recovering from MPS the PCS group (n = 54) had similar rates of postoperative complications, including 30-day mortality (7.4% vs 6.3%, P = .77), compared with the No-PCS group (n = 557). The 5-year survival was significantly lower in the PCS group compared with the No-PCS group (60% vs 72%, P = .004) and was lowest in those with PCS+MPS (46%). PCS was not a significant risk factor for in-hospital (odds ratio, 1.2; P = .63) or late (hazard ratio, 1.3; P = .27) mortality.

CONCLUSIONS

Because of severe preoperative comorbidities and the complexity of open aortic repair, in acute type A aortic dissection patients with PCS and MPS, endovascular fenestration and stenting first with delayed redo sternotomy and central aortic repair was a valid approach.

Gait speed is a preoperative indicator of postoperative events after elective proximal aortic surgery

OBJECTIVE

The study objective was to evaluate whether 5-m gait speed, an established marker of frailty, is associated with postoperative events after elective proximal aortic surgery.

METHODS

We performed a retrospective review of 435 patients aged more than 60 years who underwent elective proximal aortic surgery, defined as surgery on the aortic root, ascending aorta, or aortic arch through median sternotomy. Patients completed a 5-m gait speed test within 30 days before surgery. We evaluated the association between categoric (slow, ≤0.83 m/s and normal, >0.83 m/s) and continuous gait speed and the likelihood of experiencing the composite outcome before and after adjustment for European System for Cardiac Operative Risk Evaluation II. The composite outcome included in-hospital mortality, renal failure, prolonged ventilation, and discharge location. Secondary outcomes were 1-year mortality and 5-year survival.

RESULTS

Of the study population, 30.3% (132/435) were categorized as slow. Slow walkers were significantly more likely to have in-hospital mortality, prolonged ventilation, and renal failure, and were less likely to be discharged home (all P < .05). The composite outcome was 2 times more likely to occur for slow walkers (gait speed categoric adjusted odds ratio, 2.08; 95% confidence interval, 1.27-3.40; P = .004). Moreover, a unit (1 m/s) increase in gait speed (continuous) was associated with 73% lower risk of experiencing the composite outcome (odds ratio, 0.27; 95% confidence interval, 0.11-0.68; P = .006).

CONCLUSIONS

Slow gait speed is a preoperative indicator of risk for postoperative events after elective proximal aortic surgery. Gait speed may be an important tool to complement existing operative risk models, and its application may identify patients who may benefit from presurgical and postsurgical rehabilitation.

Type A aortic dissection complicated by malperfusion syndrome

PURPOSE OF REVIEW

Malperfusion is present in up to 40% of acute type A aortic dissections (ATAADs) and results in increased morbidity and mortality. This review presents different management strategies in patients with ATAAD and malperfusion to improve outcomes.

RECENT FINDINGS

While the ideal management strategy of ATAAD complicated by malperfusion has yet to be determined, the literature provides evidence for additional techniques to be used in conjunction with central aortic repair to reduce mortality.

SUMMARY

Recent findings support a role for initial reperfusion and delayed central aortic repair, although optimal management strategy remains debated.

Aortic progression and reintervention in patients with pathogenic variants after a thoracic aortic dissection

OBJECTIVE

To evaluate aortic disease progression and reintervention after an initial thoracic aortic dissection in pathogenic variant carriers.

METHODS

Of 175 participants diagnosed with thoracic aortic dissection, 31 had a pathogenic variant (pathogenic group) across 6 genes (COL3A1, FBN1, LOX, PRKG1, SMAD3, TGFBR2) identified by whole exome sequencing. Those with benign or normal variants (benign/normal group, n = 144) comprised the control group. Clinical data were collected through medical record review (1985-2018) and supplemented with the National Death Index database (December 2018).

RESULTS

The entire cohort (n = 175) consisted of 108 type A aortic dissections and 67 type B aortic dissections, similarly distributed between groups. The pathogenic group was significantly younger (43 vs 56 years, P < .0001) and had significantly more aortic root replacements and similar extents of arch replacement at initial type A aortic dissection repair. The median follow-up time was 7.5 (4.6-12) years. After initial treatment, the pathogenic group required significantly more aortic reinterventions (median 1 vs 0, P < .0001) and mean cumulative aortic reinterventions for each patient (10 years: 1 vs 0.5, P = .029). Both incidence rate (12%/year vs 1.2%/year, P = .0001) and cumulative incidence of reinterventions (9 years: 70% vs 6%, P < .0001) for the preserved native aortic root were significantly higher in the pathogenic group, but were similar for the preserved native aortic arch and distal aorta between groups. Ten-year survival was similar in the pathogenic and benign/normal groups (92% vs 85%).

CONCLUSIONS

Aggressive aortic root replacement and similar arch management should be considered in pathogenic variant carriers at initial type A aortic dissection repair compared with benign/normal variant carriers.

Endovascular Fenestration/Stenting First Followed by Delayed Open Aortic Repair for Acute Type A Aortic Dissection With Malperfusion Syndrome

BACKGROUND

Immediate open repair of acute type A aortic dissection is traditionally recommended to prevent death from aortic rupture. However, organ failure because of malperfusion syndrome (MPS) might be the most imminent life-threatening problem for a subset of patients.

METHODS

From 1996 to 2017, among 597 patients with acute type A aortic dissection, 135 patients with MPS were treated with upfront endovascular reperfusion (fenestration/stenting) followed by delayed open repair (OR). We compared outcomes between the first and second decades and observed mortalities with those expected with an "upfront OR for every patient" approach, determined using prognostic models from the literature (Verona, Leipzig-Halifax, Stockholm, Penn, and GERAADA [German Registry for Acute Aortic Dissection Type A] models).

RESULTS

Overall, in-hospital mortality improved between the 2 decades (21.0% versus 10.7%, P<0.001). In the second decade, for patients with MPS initially treated with fenestration/stenting, mortality from aortic rupture decreased from 16% to 4% ( P=0.05), the risk of dying from organ failure was 6.6 times higher than dying from aortic rupture (hazard ratio=6.63; 95% CI, 1.5-29; P=0.01), and 30-day mortality after OR for MPS patients was 3.7%. Compared to the expected mortalities with the upfront OR for every patient models, our observed 30-day and in-hospital mortalities (9% and 11%, respectively) of all patients with acute type A aortic dissection were significantly lower ( P≤0.03).

CONCLUSIONS

Immediate OR is the strategy to prevent death from aortic rupture for the majority of patients with acute type A aortic dissection. However, relatively stable (no rupture, no tamponade) patients with MPS benefit from a staged approach: upfront endovascular reperfusion followed by aortic OR at resolution of organ failure.

Management of acute type B aortic dissection with malperfusion via endovascular fenestration/stenting

OBJECTIVE

The study objective was to evaluate the management of malperfusion in acute type B aortic dissection with endovascular fenestration/stenting.

METHODS

From 1996 to 2018, 182 patients with an acute type B aortic dissection underwent fenestration/stenting for suspected malperfusion based on imaging, clinical manifestations, and laboratory findings. Data were obtained from medical record review and the National Death Index database.

RESULTS

The median age of patients was 55 years. Signs of malperfusion included abdominal pain (61%), lower-extremity weakness (27%), nonpalpable lower-extremity pulses (24%), and abnormal lactate, creatinine, liver enzymes, and creatine kinase levels. Confirmed hemodynamically significant malperfusion affected the spinal cord (2.7%), celiac (24%), superior mesenteric (40%), renal (51%), and iliofemoral (43%) arterial distributions. Of the 182 patients, 99 (54%) underwent aortic fenestration/stenting, 108 (59%) had 1 or multi-branch vessel fenestration/stenting, 5 (2.7%) had concomitant thoracic endovascular aortic repair, 17 (9.3%) had additional thrombolysis or thromboembolectomy, and 48 (26%) received no intervention. After fenestration/stenting, 24 patients (13%) required additional procedures for necrotic bowel or limb and 9 patients (4.9%) had subsequent aortic repair (thoracic endovascular aortic repair, open repair) before discharge. The new-onset paraplegia was 0%. The in-hospital mortality was 7.7% over 20+ years and 0% in the last 8 years. The 5- and 10-year survivals were 72% and 49%, respectively. The significant risk factors for late mortality were age and acute paralysis (hazard ratio, 3.5; both P < .0001). Given death as a competing factor, the 5- and 10-year cumulative incidence of reintervention was 21% and 31% for distal aortic pathology, respectively.

CONCLUSIONS

Patients with acute type B aortic dissection with malperfusion can be managed with endovascular fenestration/stenting with excellent short- and long-term outcomes. This approach is particularly helpful to patients with static malperfusion of aortic branch vessels.

Unilateral is comparable to bilateral antegrade cerebral perfusion in acute type A aortic dissection repair

OBJECTIVE

To compare the short- and long-term outcomes of unilateral and bilateral antegrade cerebral perfusion (uni-ACP and bi-ACP) in acute type A aortic dissection (ATAAD) repair.

METHODS

From 2001 to 2017, 307 patients underwent surgical repair of an ATAAD using uni-ACP (n = 140) and bi-ACP (n = 167). Data were collected through the Department of Cardiac Surgery Data Warehouse, medical record review, and the National Death Index database.

RESULTS

The demographics and preoperative comorbidities were similar between the uni-ACP and bi-ACP groups. Both groups had similar rates of procedures for aortic valve/root, ascending aorta, frozen elephant trunk, and other concomitant procedures. Perioperative outcomes were not significantly different between the 2 groups (30-day mortality: uni-ACP 3.4% vs bi-ACP 7.8%, P = .12) except reoperation for bleeding was significantly lower in uni-ACP (5% vs 12%, P = .03). Between the uni-ACP and bi-ACP groups, overall postoperative stroke rate (6% vs 9%, P = .4) and left brain stroke rate (0.7% vs 3.0%, P = .23) were not significantly different. The odds ratio of uni-ACP versus bi-ACP was 0.87 (P = .80) for postoperative stroke and 0.86 (P = .81) for operative mortality. The mid-term survival was better in the uni-ACP group, P = .027 (5-year: 84% vs 76%). The hazard ratio of all-time mortality for uni-ACP versus bi-ACP was 0.74 (95% confidence interval, 0.33-1.65), P = .46.

CONCLUSIONS

In ATAAD, both uni-ACP and bi-ACP are equally effective to protect the brain with low postoperative stroke rates and mortality in hemiarch to zone 3 arch replacement. Uni-ACP is recommended for its simplicity and less manipulation of arch branch vessels.

Management of malperfusion syndrome in acute type A aortic intramural hematoma

Background

We report the outcomes of acute type A aortic intramural hematoma (ATAAIMH) with malperfusion treated with endovascular intervention and delayed open aortic repair.

Methods

Between April 1998 and April 2018, 644 patients were treated at our institution with an acute type A aortic dissection (ATAAD) or ATAAIMH, 82 (13%) had intramural hematomas (IMHs) including 12 (15%) with malperfusion syndrome (MPS) and 70 (85%) without MPS (no MPS). Data was obtained through medical record review, the Society of Thoracic Surgeons data elements, and the National Death Index database.

Results

Both MPS and No MPS groups had similar comorbidities including coronary artery disease, hypertension, diabetes, and peripheral vascular disease; however, those with MPS were sicker on admission with higher rates of acute renal failure (50% vs. 1%, P<0.0001) and acute paralysis (17% vs. 0%, P=0.02). Patients with MPS amenable to endovascular reperfusion (n=10) underwent endovascular fenestration/stenting and delayed aortic repair. Those with cerebral or coronary MPS (n=2) and those without MPS (n=70) underwent emergent open aortic repair. Of the ten patients undergoing fenestration/stenting, seven went on to aortic repair, one survived to discharge without aortic repair, one died from aortic rupture on hospital day 34, and one died from organ failure prior to aortic repair. Following endovascular fenestration/stenting or aortic repair, all patients with MPS had higher in-hospital mortality (17% vs. 0%), P=0.02. Following aortic repair, patients with MPS had more postoperative sepsis and longer postoperative length of stay (all P<0.05). However, both groups had a 0% operative mortality (including in-hospital and 30-day mortality following aortic repair). The 5-year survival of all ATAAIMH patients was 79%. The 2-year survival was significantly better in the No MPS group (94% vs. 62%, P=0.006).

Conclusions

ATAAIMH with MPS can be effectively managed with upfront endovascular fenestration/stenting followed by delayed aortic repair.

Is previous cardiac surgery a risk factor for open repair of acute type A aortic dissection?

OBJECTIVE

The study objective was to determine the optimal treatment for patients with acute type A aortic dissection and previous cardiac surgery.

METHODS

A total of 545 patients underwent open repair of an acute type A aortic dissection (July 1996 to January 2017), including patients with (n = 50) and without previous cardiac surgery (n = 495). Data were collected through the University of Michigan Cardiac Surgery Data Warehouse, medical record review, and the National Death Index database.

RESULTS

Compared with patients without previous cardiac surgery, patients with previous cardiac surgery were older (62 vs 59 years, P = .24) and had significantly more coronary artery disease (48% vs 14%, P < .001), peripheral arterial disease (24% vs 11%, P = .01), connective tissue disorders (15% vs 4.5%, P = .004), and acute renal failure on presentation (28% vs 15%, P = .02); and significantly more concomitant mitral or tricuspid procedures, longer cardiopulmonary bypass time, and more intraoperative blood transfusions. There were no statistically significant differences in postoperative major complications between previous cardiac surgery and no previous cardiac surgery groups, including stroke, myocardial infarction, new-onset dialysis, and 30-day mortality (8.9% vs 6.3%, P = .55). Multivariable logistic model showed the significant risk factors for operative mortality were cardiogenic shock (odds ratio, 9.6; P < .0001) and male gender (odds ratio, 3.7; P = .006). The 5- and 10-year unadjusted survivals were significantly lower in the previous cardiac surgery group compared with the no previous cardiac surgery group (66% vs 80% and 42% vs 66%, respectively, P = .02). However, previous cardiac surgery itself was not a significant risk factor for operative mortality (odds ratio, 1.6; P = .36) or all-time mortality (hazard ratio, 1.3; P = .33).

CONCLUSIONS

Acute type A aortic dissection in patients with previous cardiac surgery can be repaired with favorable operative mortality and long-term survival, and should be treated surgically.

Clinical Implications of Identifying Pathogenic Variants in Individuals With Thoracic Aortic Dissection

BACKGROUND

Thoracic aortic dissection is an emergent life-threatening condition. Routine screening for genetic variants causing thoracic aortic dissection is not currently performed for patients or family members.

METHODS

We performed whole exome sequencing of 240 patients with thoracic aortic dissection (n=235) or rupture (n=5) and 258 controls matched for age, sex, and ancestry. Blinded to case-control status, we annotated variants in 11 genes for pathogenicity.

RESULTS

Twenty-four pathogenic variants in 6 genes (COL3A1, FBN1, LOX, PRKG1, SMAD3, and TGFBR2) were identified in 26 individuals, representing 10.8% of aortic cases and 0% of controls. Among dissection cases, we compared those with pathogenic variants to those without and found that pathogenic variant carriers had significantly earlier onset of dissection (41 versus 57 years), higher rates of root aneurysm (54% versus 30%), less hypertension (15% versus 57%), lower rates of smoking (19% versus 45%), and greater incidence of aortic disease in family members. Multivariable logistic regression showed that pathogenic variant carrier status was significantly associated with age <50 (odds ratio [OR], 5.5; 95% CI, 1.6-19.7), no history of hypertension (OR, 5.6; 95% CI, 1.4-22.3), and family history of aortic disease (mother: OR, 5.7; 95% CI, 1.4-22.3, siblings: OR, 5.1; 95% CI, 1.1-23.9, children: OR, 6.0; 95% CI, 1.4-26.7).

CONCLUSIONS

Clinical genetic testing of known hereditary thoracic aortic dissection genes should be considered in patients with a thoracic aortic dissection, followed by cascade screening of family members, especially in patients with age-of-onset <50 years, family history of thoracic aortic disease, and no history of hypertension.

Short- and long-term outcomes of aortic root repair and replacement in patients undergoing acute type A aortic dissection repair: Twenty-year experience

OBJECTIVE

The study objective was to evaluate the perioperative and long-term outcomes of aortic root repair and aortic root replacement and provide evidence for root management in acute type A aortic dissection.

METHODS

From 1996 to 2017, 491 patients underwent aortic root repair (n = 307) or aortic root replacement (n = 184) (62% bioprosthesis) for acute type A aortic dissection. Indications for aortic root replacement were intimal tear at the aortic root, root measuring 4.5 cm or more, connective tissue disease, or unrepairable aortic valvulopathy. Primary outcomes were in-hospital mortality, long-term survival, and reoperation rate for root pathology.

RESULTS

Patients' median age was 61 years and 56 years in the aortic root repair group and aortic root replacement group, respectively. The aortic root replacement group had more renal failure requiring dialysis, previous cardiac intervention or surgery, heart failure, coronary malperfusion syndrome, acute myocardial infarction, and severe aortic insufficiency, as well as concomitant coronary artery bypass grafting, tricuspid valve repair, and longer cardiopulmonary bypass and aortic crossclamp times but similar arch procedures. Perioperative outcomes were similar in the aortic root repair and aortic root replacement groups, including in-hospital mortality (8.5% and 8.2%), new-onset renal failure requiring permanent dialysis, stroke, myocardial infarction, and sepsis. Kaplan-Meier 10-year survival was 62% and 65%, and the 15-year cumulative incidence of reoperation was 11% and 7% in the aortic root repair and aortic root replacement groups, respectively. The primary indication for root reoperation was aortic root aneurysm in the aortic root repair group and bioprosthetic valve deterioration in the aortic root replacement group.

CONCLUSIONS

Aortic root repair and aortic root replacement are appropriate surgical options for acute type A aortic dissection repair with favorable short- and long-term outcomes. Aortic root replacement should be performed for patients with acute type A aortic dissection presenting with an intimal tear at the aortic root, root aneurysm 4.5 cm or greater, connective tissue disease, or unrepairable aortic valvulopathy.

Late outcomes of strategic arch resection in acute type A aortic dissection

OBJECTIVE

To compare perioperative and long-term outcomes in patients undergoing hemiarch and aggressive arch replacement for acute type A aortic dissection (ATAAD).

METHODS

From 1996 to 2017, we compared outcomes of hemiarch (n = 322) versus aggressive arch replacements (zones 2 and 3 arch replacement with implantation of 2-4 arch branches, n = 150) in ATAAD. Indications for aggressive arch were arch aneurysm >4 cm or intimal tear in the aortic arch that was not resectable by hemiarch replacement, or dissection of arch branches with malperfusion.

RESULTS

Patients in the aggressive arch group were significantly younger (mean age: 57 vs 61 years old) and had significantly longer hypothermic circulatory arrest, cardiopulmonary bypass, and aortic crossclamp times. There were no significant differences in perioperative outcomes between hemiarch and aggressive arch groups, including 30-day mortality (5.3% vs 7.3%, P = .38) and postoperative stroke rate (7% vs 7%, P = .96). Over 15 years, Kaplan-Meier survival was similar between hemiarch and aggressive arch groups (log-rank P = .55, 10-year survival 70% vs 72%). Given death as a competing factor, incidence rates of reoperation over 15 years (2.1% vs 2.0% per year, P = 1) and 10-year cumulative incidence of reoperation (14% vs 12%, P = .89) for arch and distal aorta pathology were similar between the 2 groups.

CONCLUSIONS

Both hemiarch and aggressive arch replacement are appropriate approaches for select patients with ATAAD. Aggressive arch replacement should be considered for an arch aneurysm >4 cm or an intimal tear at the arch unable to be resected by hemiarch replacement, or dissection of the arch branches with malperfusion.

Induced pluripotent stem cells with NOTCH1 gene mutation show impaired differentiation into smooth muscle and endothelial cells: Implications for bicuspid aortic valve-related aortopathy

OBJECTIVE

The NOTCH1 gene mutation has been identified in bicuspid aortic valve patients. We developed an in vitro model with human induced pluripotent stem cells (iPSCs) to evaluate the role of NOTCH1 in smooth muscle and endothelial cell (EC) differentiation.

METHODS

The iPSCs were derived from a patient with a normal tricuspid aortic valve and aorta. The NOTCH1 gene was targeted in iPSCs with the Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated protein 9 nuclease (Cas9) system. The NOTCH1^-/- (NOTCH1 homozygous knockout) and isogenic control iPSCs (wild type) were differentiated into neural crest stem cells (NCSCs) and into cardiovascular progenitor cells (CVPCs). The NCSCs were differentiated into smooth muscle cells (SMCs). The CVPCs were differentiated into ECs. The differentiations of SMCs and ECs were compared between NOTCH1^-/- and wild type cells.

RESULTS

The expression of NCSC markers (SRY-related HMG-box 10 and transcription factor AP-2 alpha) was significantly lower in NOTCH1^-/-NCSCs than in wild type NCSCs. The SMCs derived from NOTCH1^-/- NCSCs showed immature morphology with smaller size and decreased expression of all SMC-specific contractile proteins. In NOTCH1^-/-CVPCs, the expression of ISL1, NKX2.5, and MYOCD was significantly lower than that in isogenic control CVPCs, indicating impaired differentiation from iPSCs to CVPCs. The NOTCH1^-/-ECs derived from CVPCs showed significantly lower expression of cluster of differentiation 105 and cluster of differentiation 31 mRNA and protein, indicating a defective differentiation process.

CONCLUSIONS

NOTCH1 is critical in SMC and EC differentiation of iPSCs through NCSCs and CVPCs, respectively. NOTCH1 gene mutations might potentially contribute to the development of thoracic aortic aneurysms by affecting SMC differentiation in some patients with bicuspid aortic valve.

Short-term outcomes of a simple and effective approach to aortic root and arch repair in acute type A aortic dissection

OBJECTIVE

To evaluate short-term outcomes following direct aortic root and arch repair in patients with acute type A aortic dissection (ATAAD) without technical adjuncts.

METHODS

Between 2012 and 2016, 94 consecutive patients with ATAAD underwent surgical repair, including aortic root repair (n = 45), root replacement (n = 39), or no root procedure (n = 10). Aortic root repair was achieved by running approximation of the dissected aortic wall circumferentially at the sinotubular junction and reinforcing the coronary ostia with 5-0 Prolene. The aortic root and arch were anastomosed to the Dacron graft with 5-0 Prolene without Teflon felt or biological glue.

RESULTS

Postoperative new-onset myocardial infarction, stroke, renal failure, and complete heart block occurred in 0%, 4%, 13%, and 0% of patients, respectively, whereas 30-day mortality was 4%. The incidences of permanent neurologic deficit and renal failure were 1% and 2%, respectively. Up to 5 years, the aortic root repair group was free from residual or recurrent aortic root dissection, major change in the aortic root diameter, and moderate to severe aortic regurgitation; the entire cohort was free of anastomotic pseudoaneurysm and reoperation for proximal aortic pathology or significant change in diameter of the aortic arch and descending thoracic aorta. Overall survival was 85% at 4 years and was significantly enhanced in the aortic root repair group compared with the Bentall group (n = 24) (93% vs 57%; P = .035).

CONCLUSIONS

Direct aortic root and arch repair with approximation of the aortic wall without use of technical adjuncts is safe and effective for patients with ATAAD. If warranted, preservation of the native aortic valve should be considered for a potential survival benefit.