Acute type A intramural hematoma: The less-deadly acute aortic syndrome?

OBJECTIVE: To evaluate the short- and midterm outcomes of surgically managed acute type A intramural hematoma (IMH) versus classic acute type A aortic dissection (ATAAD). METHODS: From 1996 to February 2023, a total of 106 patients with acute type A IMH and 795 patients with classic ATAAD presented for open aortic repair at our institution. Data were obtained from the local Society of Thoracic Surgeons' Data Warehouse and medical chart review. RESULTS: Compared with the classic ATAAD group, the IMH group was older (65 vs 59 years, P < .001) and more likely to be female (45% vs 32%, P = .005), with fewer comorbidities such as severe aortic insufficiency (5.0% vs 25%, P < .001), acute stroke (2.8% vs 8.3%, P = .05), acute renal failure (5.7% vs 13%, P = .04), and malperfusion syndrome (8.5% vs 26%, P < .001) but more cardiac tamponade (18% vs 11%, P = .03). The IMH group had less aortic root replacement (15% vs 33%, P < .001), zone 2 arch replacements (9.4% vs 18%, P = .02), and shorter crossclamp times (120 minutes vs 150 minutes, P < .001). The operative mortality was significantly lower in the IMH group (0.9% vs 8.8%, P = .005) and a multivariable regression model showed IMH to be protective, odds ratio of 0.11, P = .03. The 10-year survival was similar between the 2 groups (65% vs 61%, P = .35). The hazard ratio of IMH for midterm mortality after surgery was 0.73, P = .12. CONCLUSIONS: Acute type A IMH could be treated with emergency open aortic repair with excellent short- and midterm outcomes.

Progression of distal aorta after endovascular fenestration/stenting in acute type A aortic dissection with malperfusion syndrome.

Objective: The study objective was to evaluate the progression of dissected distal aorta in patients with acute type A aortic dissection with malperfusion syndrome treated with endovascular fenestration/stenting and delayed open aortic repair. Methods: From 1996 to 2021, 927 patients presented with acute type A aortic dissection. Of these, 534 had DeBakey I dissection with no malperfusion syndrome and underwent emergency open aortic repair (no malperfusion syndrome group), whereas 97 patients with malperfusion syndrome underwent fenestration/stenting and delayed open aortic repair (malperfusion syndrome group). Sixty-three patients with malperfusion syndrome treated with fenestration/stenting were excluded due to no open aortic repair, including death from organ failure (n = 31), death from aortic rupture (n = 16), and discharged alive (n = 16). Results: Compared with the no malperfusion syndrome group, the malperfusion syndrome group had more patients with acute renal failure (60% vs 4.3%, P < .001). Both groups had similar aortic root and arch procedures. Postoperatively, the malperfusion syndrome group had similar operative mortality (5.2% vs 7.9%, P = .35) and permanent dialysis (4.7% vs 2.9%, P = .50), but more new-onset dialysis (22% vs 7.7%, P < .001) and prolonged ventilation (72% vs 49%, P < .001). The growth rate of the aortic arch (0.38 vs 0.35 mm/year, P = .81) was similar between the malperfusion syndrome and no malperfusion syndrome groups. The descending thoracic aorta growth rate (1.03 vs 0.68 mm/year, P = .001) and abdominal aorta growth rate (0.76 vs 0.59 mm/year, P = .02) were significantly higher in the malperfusion syndrome group. The cumulative incidence of reoperation over 10 years (18% vs 18%, P = .81) and 15-year survival outcome (50% vs 48%, P = .43) were similar between the malperfusion syndrome and no malperfusion syndrome groups. Conclusions: Endovascular fenestration/stenting followed by delayed open aortic repair was a valid approach for patients with malperfusion syndrome.

Valve-Sparing Aortic Root Replacement Technique: Valsalva Graft versus Two Straight Tubular Grafts.

Background: There are many variations in valve-sparing aortic root replacement techniques. Our aim is to determine the impact of the graft on mid-term outcomes: Valsalva graft vs. two straight tubular grafts. Methods: From 2004 to 2020, 332 patients underwent valve-sparing aortic root replacement with either a Valsalva graft (Valsalva group: n = 270) or two straight tubular grafts (two-graft group: n = 62). Data were obtained through chart review and the National Death Index. Primary outcomes were mid-term survival and freedom from reoperation. Results: The preoperative characteristics of the groups were similar, but the two-graft group had more type A dissections (32% vs. 19%) and emergent operations (26% vs. 15%) and was younger (45 vs. 50 years). Intraoperatively, the groups were similar, but the two-graft group had longer cross-clamp (245 vs. 215 minutes) and cardiopulmonary bypass times (284 vs. 255 minutes). Postoperative complications including reoperation for bleeding, stroke, pacemaker implantation, and renal failure were slightly more frequent in the Valsalva group, but the differences were not significant. Operative mortality was similar between the Valsalva and two-graft groups (0.7% vs. 0%). Five-year survival in the two-graft group was 100% compared to 96% in the Valsalva group (p=0.56). Five-year freedom from reoperation in the two-graft group was 100% compared to 93% in the Valsalva group (p=0.29). Conclusions: The Valsalva and two-graft techniques both have excellent short- and mid-term outcomes. The two-graft technique might have slightly better survival and freedom from reoperation, but a larger sample size and longer follow-up are needed to determine if these advantages are significant.

Distal Aortic Progression After Hemiarch, Zones 1-3 Arch Replacement in Acute Type A Aortic Dissection.

BACKGROUND: There is debate regarding aortic arch repair extent for acute type A aortic dissection (ATAAD) patients. METHODS: From 1996 to 2021, 756 ATAAD patients underwent open arch replacement. The cohort was divided into hemiarch (n = 481), zone 1 (n = 65), zone 2 (n = 148), and zone 3 (n = 62) arch replacement groups. Cross-group comparison of aortic growth was modeled using data from interval postoperative computed tomography or magnetic resonance imaging of the distal aorta. RESULTS: Demographics were not significantly different except the hemiarch group had more coronary artery disease and less stroke. Intraoperatively, zones 1, 2, and 3 had greater cardiopulmonary bypass, cross-clamp, and hypothermic circulatory arrest times and required more intraoperative blood transfusion than the hemiarch group. Perioperative outcomes were similar among groups except zone 3 had more reoperation for bleeding. Ten-year cumulative incidence of reoperation was hemiarch, 16.7%; zone 1, 16.3%; zone 2, 21.5%; and zone 3, 17.6% (P = .70). Ten-year survival was similar: hemiarch, 66%; zone 1, 60.3%; zone 2, 68.0%); and zone 3 66.1% (P = .20). Aortic arch, descending aorta, and abdominal aorta growth rates were not significantly different among groups over 10 years. In the whole cohort, the growth rate over time for aortic arch was 0.38 mm per year (P < .001), descending aorta 0.84 mm per year (P < .001), and abdominal aorta 0.69 mm per year (P < .001). CONCLUSIONS: There was no significant difference in long-term survival, distal aorta growth, or reoperation rate for distal aortic aneurysm after hemiarch or zones 1, 2, or 3 arch replacement. Patient-specific arch replacement strategies may be used rather than defaulting to aggressive arch replacement for all ATAAD patients.

Midterm outcomes of open repair versus endovascular descending thoracic aortic aneurysm repair.

Objective: The study objective was to evaluate the midterm outcome of thoracic endovascular aortic repair compared with open repair in patients with descending thoracic aortic aneurysm. Methods: From August 1993 to February 2023, 499 patients with descending thoracic aortic aneurysms underwent open repair (n = 221) or thoracic endovascular aortic repair (n = 278). Of these, 120 matched pairs were identified using propensity score matching based on age, sex, chronic lung disease, stroke, coronary artery disease, diabetes, ejection fraction, dialysis, peripheral vascular disease, prior cardiac surgery, connective tissue disease, and chronic dissection. Primary outcomes were postoperative paralysis, operative mortality, reoperation, and midterm survival. Results: After matching, the preoperative demographics and comorbidities were balanced in both groups. Intraoperatively, open repair had a lower temperature (18 °C vs 36 °C) and more patients required blood products (66% vs 8%), P < .001. Postoperatively, patients undergoing thoracic endovascular aortic repair had fewer strokes (2.5% vs 9.2%; P = .03), less dialysis (0% vs 3.3%; P = .04), and shorter length of stay (5 days vs 12 days, P < .001), but similar lower-extremity paralysis (2.5% vs 2.5%, P = 1.00) compared with open repair. Furthermore, thoracic endovascular aortic repair had higher 7-year incidence of first reoperation (16.1% vs 3.6%, P < .001) but similar operative mortality (0.8% vs 4.2%; P = .10) and 10-year survival outcome (56%; 95% CI, 43-72 vs 58%; 95% CI, 49-68; P = .55) compared with open aortic repair. The hazard ratio was 0.93 (P = .78) for thoracic endovascular aortic repair for midterm mortality and 6.87 (P < .001) for reoperation. Conclusions: Open repair could be the first option for patients with descending thoracic aortic aneurysms who were surgical candidates.

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.

Contemporary nonsurgical management of acute type A aortic dissection: Better outcomes?

OBJECTIVE: The objective of this study was to evaluate outcomes of nonsurgically managed acute type A aortic dissection (ATAAD) in the contemporary era. METHODS: From January 1996 to December 2021, 999 patients presented with ATAAD at our institution, of whom 839 patients underwent open aortic repair (surgical cohort) whereas 148 patients were managed nonoperatively (nonsurgical cohort) because of severe comorbidities, organ failure from malperfusion syndrome, and patients' wishes. Data were obtained from chart review, the Society of Thoracic Surgeons warehouse, the national death index, and Michigan death index database. RESULTS: The combined in-hospital + 30-day mortality rate was 9 times higher in the nonsurgical cohort compared with the surgical cohort (70% vs 7.9%). In the nonsurgical cohort, compared with the first decade (1996-2010), patients during the second decade (2011-2021) had a lower in-hospital+30-day mortality rate (58% vs 87%; P<.001); lower incidence of aortic rupture (8% vs 21%; P=.008), and a higher 3-year survival rate (29% vs 13%; P=.005). Within the nonsurgical cohort, compared with patients without malperfusion syndrome, the patients with malperfusion syndrome had similar in-hospital + 30-day mortality but a greater incidence of aortic rupture (21% vs 6.1%, P=.01) with an odds ratio of 4.2 (P=.03); compared with classic type A dissection, the patients with intramural hematoma had a lower in-hospital+30-day mortality rate (52% vs 72%, P=.02) with an odds ratio of 0.36 (P=.02). CONCLUSIONS: Surgery remained the mainstream treatment for ATAAD. Nonsurgical management still had a role for those who were not surgical candidates because of comorbidities or malperfusion syndrome, especially in those with acute type A intramural hematoma.

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.

Progression of aortic root based on long-term imaging studies after acute type A dissection repair.

BACKGROUND: To determine the progression of aortic root in acute type A aortic dissection (ATAAD) patients after aortic root repair (ARr) or replacement (ARR) based on long-term follow-up imaging studies. METHODS: From 1996 to 2019, 732 patients had ATAAD repair at our institution. Six hundred and seven of these patients had either ARr, (n = 383) or ARR (n = 224). Eighty-one patients were excluded due to a lack of postoperative imaging. Three hundred and thirty-two patients were included in the repair group and 194 patients in the replacement group for long-term follow-up imaging study. RESULTS: Compared to the ARR group, the ARr group was significantly older (60 years vs. 55 years) and had more patients with hypertension (79% vs. 63%) but less male patients (63% vs. 79%) and connective tissue disorder (1.8% vs 8%). The ARr group had more zone two arch replacement (22% vs. 11%), similar HCA time (35 min vs. 31 min), shorter cardiopulmonary bypass time (203 min vs. 266 min), aortic cross-clamp time (128 min vs. 214 min), and fewer concomitant coronary artery bypass (3.9% vs. 8.9%). The root growth rate over 12 years was similar between the repair and replacement group (0.20 mm/year vs. 0.18 mm/year, p = .75). Both the repair and replacement group had similar 15-year cumulative incidence of reoperation (6.9% vs. 5.9%; p = .67), operative mortality (7.8% vs. 8.5%; p = .78), and 15-year survival (51% vs. 52%; p = .40). CONCLUSIONS: There was minimal growth of the aortic root after root repair or replacement for ATAAD patients. Both aortic root repair and replacement were acceptable techniques for ATAAD surgery in select patients.

Aortic root repair in acute type A aortic dissection: Neomedia or no neomedia.

OBJECTIVE: Neomedia has been frequently used for aortic root repair in acute type A aortic dissection. We aimed to determine the efficacy and necessity of neomedia during acute type A aortic dissection root repair. METHODS: From January 2010 to February 2021, 308 patients with acute type A aortic dissection underwent aortic root repair with neomedia (n = 132) or without neomedia (n = 176). Of these, 121 matched pairs were identified using propensity score matching based on age, sex, coronary artery disease, preoperative renal failure, acute stroke, prior cardiac surgery, cardiogenic shock, coronary malperfusion, preoperative cardiopulmonary resuscitation, and severe aortic insufficiency. RESULTS: After matching, the preoperative demographics and comorbidities were well balanced in both groups. Compared with the neomedia group, the no neomedia group had less hemiarch (57% vs 69%, P = .05) and more zone 1 arch replacements (12% vs 4.1%, P = .03), shorter hypothermic circulatory arrest time (28 vs 36 minutes, P < .001), and shorter crossclamp time (120 vs 131 minutes, P = .02). Postoperative outcomes were similar, and the odds ratio by univariable logistic model of no neomedia for operative mortality was 0.83 (P = .76). Aortic root growth over 11 years (0.11 vs 0.16 mm/year, P = .66), 5-year freedom from greater than mild aortic insufficiency (84% vs 85%, P = .80), reoperation for root pathology (1 patient in each group), and 8-year survival (80% [95% confidence interval, 69-97] vs 71% [95% confidence interval, 55-82], P = .26) were similar between the neomedia and no neomedia groups. CONCLUSIONS: In patients with acute type A aortic dissection, aortic root repair with or without neomedia was equally safe and effective. Neomedia use could be avoided in acute type A aortic dissection repair.

Distal aortic progression following acute type A aortic dissection repair among patients with bicuspid and tricuspid aortic valves.

OBJECTIVE: The study objective was to analyze long-term growth and outcomes of the distal aorta after open acute type A aortic dissection repair in patients with bicuspid aortic valves or tricuspid aortic valves without connective tissue disease. METHODS: From 1996 to 2021, 60 patients with bicuspid aortic valves and 655 patients with tricuspid aortic valves without connective tissue disease underwent open repair for acute type A aortic dissection. Data were collected from the local Society of Thoracic Surgeons database, medical record review, surveys, and the National Death Index and Michigan Death Index (December 12, 2021). RESULTS: Compared with the tricuspid aortic valve group, the bicuspid aortic valve group was significantly younger, had more severe aortic insufficiency (33% vs 22%, P = .05), and had less hypertension (67% vs 78%, P = .05). Intraoperatively, patients with bicuspid aortic valves received more aortic root replacements (70% vs 26%, P < .001), less zone 2 aortic arch replacement (8.3% vs 20%, P = .03), and longer median cardiopulmonary bypass (233 vs 214 minutes, P = .05) and aortic crossclamp (184 vs 141 minutes, P < .001) times. The average annual aortic arch growth rate (0.23 mm/year vs 0.39 mm/year, P = .52) and descending aorta growth rate (0.61 mm/year vs 0.79 mm/year, P = .39) were similar between the bicuspid aortic valve and tricuspid aortic valve groups. The bicuspid aortic valve group had lower annual abdominal aorta growth (0.51 mm/year vs 0.68 mm/year, P = .03). The cumulative incidence of reoperation for the distal aorta (9.7% vs 16.0%, P = .77) was similar between the bicuspid aortic valve and tricuspid aortic valve groups. The 10-year survival was higher in the bicuspid aortic valve group (75.4% vs 66.0%, P = .03). CONCLUSIONS: Patients with bicuspid aortic valves could be treated similarly as patients with tricuspid aortic valves without connective tissue disease in the setting of open acute type A aortic dissection repair.

Should We Operate on Thoracic Aortic Aneurysm of 5-5.5cm in Bicuspid Aortic Valve Disease Patients?

BACKGROUND: This study aims to determine the long-term outcomes and rate of reoperation among BAV patients with aortic diameter of 5-5.5cm who underwent immediate surgical repair versus surveillance. METHODS: A total of 148 BAV patients with aortic aneurysm measuring 5-5.5cm were identified between 1993 to 2019. Patients were categorized into two groups: immediately operated (n=89), versus watched group (n=59) i.e., monitored until either symptomatic, aortic diameter ≥ 5.5 cm or operated at surgeons' discretion/patient preference. RESULTS: Compared to the immediately operated group the watched group had significantly lower proportion of proximal aorta replacement (86% vs 100%). The mean size of proximal thoracic aorta at initial encounter, including aortic root, ascending, and arch, for the watched group was 52.1 ± 1.62mm and 52.6 ± 1.81mm in the immediately operated group, p=0.06. There was no significant difference in 10-year survival between the watched group 94% (95% CI: 79%, 99%) vs immediately operated group 96.5% (95% CI: 86%, 99%), p=0.90. Initial operation rate for the watched group during 10-year follow-up was 85%. The operative mortality in both groups was 0%. The 10-year reoperation rate between groups was similar: 3.5% (95% CI: 0.9%, 9.1%) in the immediately operated group vs 7.7% (95% CI: 2.4%, 17.1%) in the patients who eventually had surgery in the watched group, p= 0.30. CONCLUSIONS: Our study showed that the rate of reoperation was similar between groups and survival outcomes were acceptable in observed asymptomatic BAV patients without significant family history and with proximal aortic diameter of 5-5.5cm.