Surgery for type A intramural hematoma: a systematic review of clinical outcomes

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.

Medically Managed Type A Thoracic Intramural Hematoma and Penetrating Aortic Ulcer

Intramural hematoma (IMH) and a penetrating aortic ulcer (PAU) are included in a larger category of disorders termed acute aortic syndromes. These disorders typically involve the thoracic aorta, abdominal aorta, or both, and often require emergent evaluation and treatment. Both IMH and PAU, much like aortic dissection, are classified using the Stanford and DeBakey systems to indicate the aortic area involved, with Stanford type A (DeBakey type I and II) necessitating surgical intervention, and Stanford type B sufficing with medical management of blood pressure. While IMH and PAU share many characteristics of aortic dissection in terms of diagnosis and initial management, there is much controversy surrounding ultimate treatment. In this report, we describe a case of a Stanford type A IMH with associated PAU that was managed medically with a good outcome.

Outcome Comparison Between Open and Endovascular Aortic Repair for Retrograde Type A Intramural Hematoma With Intimal Tear in the Descending Thoracic Aorta: A Retrospective Observational Study

Objective: The optimal treatment modality for retrograde type A intramural hematoma (IMH) remains debatable. This study evaluated and compared surgical outcomes and aortic remodeling after open aortic repair and thoracic endovascular aortic repair (TEVAR) in patients with retrograde type A IMH with a primary intimal tear or ulcer like projection in the descending aorta.

Methods: A single center, retrospective observational study was performed on patients with retrograde type A IMH undergoing either open aortic repair and TEVAR. From June 2009 and November 2019, 46 patients with retrograde type A IMH who received either open aortic repair or TEVAR at our institution were reviewed for clinical outcomes, including post-operative mortality/morbidity, re-intervention rate and aortic remodeling.

Results: 33 patients underwent open aortic repair and 13 underwent TEVAR. Median age was 68 years (interquartile range [IQR] 15.2 years) and 63 years (IQR 22.5 years) for the open repair group and TEVAR group, respectively. The median duration of follow-up for TEVAR patients was 37.6 months and 40.3 months for open aortic repair. No difference in the 5-year estimated freedom from all-cause mortality (82.1 vs. 87.8%, p = 0.34), re-intervention (82.5 vs. 93.8%, p = 0.08), and aortic-related mortality (88.9 vs. 90.9%, p = 0.88) were observed between the TEVAR and open repair group, respectively; however, the open repair group had a significantly higher 30-day composite morbidity (39.4 vs. 7.7%, p = 0.037). All patients from both treatment groups had complete resolution of the IMH in the ascending aorta. With regard to the descending thoracic aorta, TEVAR group had a significantly greater regression in the diameter of the false lumen or IMH thickness when compared to the open repair group [median 14mm (IQR 10.1) vs. 5mm (IQR 9.5), p < 0.001].

Conclusion: TEVAR and open aortic repair were both effective treatments for retrograde type A IMH, in which no residual ascending aortic IMH was observed during follow-up. TEVAR was also associated with lower post-operative composite morbidities and better descending aortic remodeling. In selected patients with retrograde type A IMH, TEVAR might be a safe, effective alternative treatment modality.

Note the descending aorta: predictors of postoperative major adverse aortic event in pure acute type A intramural hematoma

Background

Intramural hematomas (IMHs) may originate from small intimal tears. Although most surgeries for acute type A IMH are conventionally performed solely at the proximal aorta, regardless of the primary intimal tear site, the remnant aortic remodeling stays important during the follow-up period after surgery.

Methods

Forty-seven patients with “pure” acute type A IMHs who underwent surgery from January 2008 to December 2019 were retrospectively analyzed. Acute type A IMH in the entire region without penetrating aortic ulcer (PAU) and aortic dissection (AD), which upon initial computed tomography (CT), can be considered as an intimal tear site, was defined as “pure” type. The maximal diameter of the aorta, maximal thickness of the IMH, and hematoma thickness ratio (HTR) of the ascending and descending aortae were measured from the preoperative computed tomographic scan. The hematoma thickness index was defined as the HTR of the descending aorta divided by that of the ascending aorta. Major adverse aortic events (MAAEs) were defined as AD, rupture, or newly developed PAU and aortic death. Predictors for postoperative MAAEs were analyzed using preoperative computed tomographic findings.

Results

The measurements of the descending aorta were larger and those of the ascending aorta were smaller in the MAAEs group, than in the corresponding other. The hematoma thickness index was significantly higher in the group with MAAEs, than in the group without; this variable was an independent predictor of MAAEs. During surgery, intimal tears were found in 16/47 (34%) patients. The hematoma thickness index was significantly smaller in the group with intimal tears than in the group without the tears. The aortic measurement appears to reflect the tear site.

Conclusions

Hematoma thickness index was an independent predictor of MAAE after acute type A IMH surgery. Long-term periodical follow-up with early reintervention may, therefore, be necessary to improve outcome in these patients. As the optimal treatment method is still controversial, inferring the location of the primary tear through the hematoma thickness index can be helpful in determining the treatment method.