Vincenzo Rampoldi

Role and Results of Surgery in Acute Type B Aortic Dissection Insights From the International Registry of Acute Aortic Dissection (IRAD)

Background— The clinical profiles and outcomes of patients treated surgically for acute type B aortic dissection (ABAD) are often reported for those in small series or for those cared for at a single institution over a long time period, during which a continuous evolution in techniques has occurred. Accordingly, we sought to evaluate the clinical features and surgical results of patients enrolled in the International Registry of Acute Aortic Dissection by identifying primary factors that influenced surgical outcome and estimating average surgical mortality for ABAD in the current era. Methods and Results— A comprehensive analysis of 290 clinical variables and their relation to surgical outcomes for 82 patients who required surgery for ABAD (from a population of 1256 patients; mean±SD age, 60.6±15.0 years; 82.9% male) and who were enrolled in the International Registry of Acute Aortic Dissection was performed. The overall in-hospital mortality was 29.3%. Factors associated with increased surgical mortality based on univariate analysis were preoperative coma or altered consciousness, partial thrombosis of the false lumen, evidence of periaortic hematoma on diagnostic imaging, descending aortic diameter >6 cm, right ventricle dysfunction at surgery, and shorter time from the onset of symptoms to surgery. Factors associated with favorable outcomes included radiating pain, normotension at surgery (systolic blood pressure 100 to 149 mm Hg), and reduced hypothermic circulatory arrest time. The 2 independent predictors of surgical mortality were age >70 years (odds ratio, 4.32; 95% confidence interval, 1.30 to 14.34) and preoperative shock/hypotension (odds ratio, 6.05; 95% confidence interval, 1.12 to 32.49). Conclusions— The present study provides insights into current-day clinical profiles and surgical outcomes of ABAD. Knowledge about different preoperative clinical conditions may help surgeons in making treatment decisions among these high-risk patients.

Role of age in acute type A aortic dissection outcome: report from the International Registry of Acute Aortic Dissection (IRAD).

OBJECTIVE The increasing life expectancy of the population will likely be accompanied by a rise in the incidence of acute type A aortic dissection. However, because of an increased risk of cardiac surgery in an elderly population, it is important to define when, if at all, the risks of aortic repair outweigh the risk of death from unoperated type A aortic dissection. METHODS We analyzed 936 patients with type A aortic dissection enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2004. Patients with type A aortic dissection were categorized according to patient age by decade and by surgical versus medical management, and outcomes of both management types were investigated in the different age groups. RESULTS The rate of surgical aortic repair decreased progressively with age, whereas surgical mortality significantly increased with age. Age 70 years or more was an independent predictor for mortality (38.2% vs 26.0%; P < .0001, odds ratio 1.73). The in-hospital mortality rate was significantly lower after surgical management compared with medical management until the age of 80 years. For patients aged 80 to 90 years, the in-hospital mortality appeared to be lower after surgical management (37.9% vs 55.2%; P = .188); however, this failed to reach clinical significance owing to the limited patient number in this age group. CONCLUSIONS Although the surgical mortality significantly increased with increased age, surgical management was still associated with significantly lower in-hospital mortality rates compared with medical management until the age of 80 years. Surgery may decrease the in-hospital mortality rate for octogenarians with type A aortic dissection and might be considered in all patients with type A aortic dissection regardless of age.

Usefulness of pulse deficit to predict in-hospital complications and mortality in patients with acute type A aortic dissection

Vascular compromise seen with pulse deficits is common in patients with type A dissection. However, patient characteristics and in-hospital outcomes associated with pulse deficits have not been evaluated. Accordingly, we studied 513 patients (mean age 62 +/- 14 years, 65% men) with acute type A aortic dissection enrolled in the International Registry of Acute Aortic Dissection. Pulse deficits, defined as decreased or absent carotid or peripheral pulses as noted by clinicians and later confirmed by diagnostic imaging, at surgery or at autopsy were noted in 154 patients (30%). Age <70 years, male gender, neurologic deficit(s), altered mental status, and hypotension, shock, or tamponade on admission were all significantly higher in patients with than without pulse deficits. The etiology of aortic dissection, clinical symptoms, and imaging findings were similar in the 2 groups. In-hospital complications (hypotension, coma, renal failure, and limb ischemia) and mortality (41% vs 25%, p = 0.0002) were significantly higher in patients with pulse deficit. Cox proportional-hazards regression analysis identified pulse deficit as an independent predictor of 5-day in-hospital mortality (risk ratio 2.73, 95% confidence interval 1.7 to 4.4; p <0.0001). Further, overall mortality rates increased with an increasing number of pulse deficits (p for trend <0.0001). Pulse deficits are common findings in patients with type A aortic dissection and identify those at high risk of in-hospital adverse events. This simple clinical sign should direct physicians to consider a diagnosis of aortic dissection in patients with acute chest pain, and should help identify a subgroup of patients who would benefit from more aggressive strategies.

Importance of Refractory Pain and Hypertension in Acute Type B Aortic Dissection Insights From the International Registry of Acute Aortic Dissection (IRAD)

Background— In patients with acute type B aortic dissection, presence of recurrent or refractory pain and/or refractory hypertension on medical therapy is sometimes used as an indication for invasive treatment. The International Registry of Acute Aortic Dissection (IRAD) was used to investigate the impact of refractory pain and/or refractory hypertension on the outcomes of acute type B aortic dissection. Methods and Results— Three hundred sixty-five patients affected by uncomplicated acute type B aortic dissection, enrolled in IRAD from 1996 to 2004, were categorized according to risk profile into 2 groups. Patients with recurrent and/or refractory pain or refractory hypertension (group I; n=69) and patients without clinical complications at presentation (group II; n=296) were compared. “High-risk” patients with classic complications were excluded from this analysis. The overall in-hospital mortality was 6.5% and was increased in group I compared with group II (17.4% versus 4.0%; P =0.0003). The in-hospital mortality after medical management was significantly increased in group I compared with group II (35.6% versus 1.5%; P =0.0003). Mortality rates after surgical (20% versus 28%; P =0.74) or endovascular management (3.7% versus 9.1%; P =0.50) did not differ significantly between group I and group II, respectively. A multivariable logistic regression model confirmed that recurrent and/or refractory pain or refractory hypertension was a predictor of in-hospital mortality (odds ratio, 3.31; 95% confidence interval, 1.04 to 10.45; P =0.041). Conclusions— Recurrent pain and refractory hypertension appeared as clinical signs associated with increased in-hospital mortality, particularly when managed medically. These observations suggest that aortic intervention, such as via an endovascular approach, may be indicated in this intermediate-risk group. # Clinical Perspective {#article-title-24}Background— In patients with acute type B aortic dissection, presence of recurrent or refractory pain and/or refractory hypertension on medical therapy is sometimes used as an indication for invasive treatment. The International Registry of Acute Aortic Dissection (IRAD) was used to investigate the impact of refractory pain and/or refractory hypertension on the outcomes of acute type B aortic dissection. Methods and Results— Three hundred sixty-five patients affected by uncomplicated acute type B aortic dissection, enrolled in IRAD from 1996 to 2004, were categorized according to risk profile into 2 groups. Patients with recurrent and/or refractory pain or refractory hypertension (group I; n=69) and patients without clinical complications at presentation (group II; n=296) were compared. “High-risk” patients with classic complications were excluded from this analysis. The overall in-hospital mortality was 6.5% and was increased in group I compared with group II (17.4% versus 4.0%; P=0.0003). The in-hospital mortality after medical management was significantly increased in group I compared with group II (35.6% versus 1.5%; P=0.0003). Mortality rates after surgical (20% versus 28%; P=0.74) or endovascular management (3.7% versus 9.1%; P=0.50) did not differ significantly between group I and group II, respectively. A multivariable logistic regression model confirmed that recurrent and/or refractory pain or refractory hypertension was a predictor of in-hospital mortality (odds ratio, 3.31; 95% confidence interval, 1.04 to 10.45; P=0.041). Conclusions— Recurrent pain and refractory hypertension appeared as clinical signs associated with increased in-hospital mortality, particularly when managed medically. These observations suggest that aortic intervention, such as via an endovascular approach, may be indicated in this intermediate-risk group.

Endovascular Repair of Acute Uncomplicated Aortic Type B Dissection Promotes Aortic Remodelling: 1 Year Results of the ADSORB Trial

OBJECTIVES Uncomplicated acute type B aortic dissection (AD) treated conservatively has a 10% 30-day mortality and up to 25% need intervention within 4 years. In complicated AD, stent grafts have been encouraging. The aim of the present prospective randomised trial was to compare best medical treatment (BMT) with BMT and Gore TAG stent graft in patients with uncomplicated AD. The primary endpoint was a combination of incomplete/no false lumen thrombosis, aortic dilatation, or aortic rupture at 1 year. METHODS The AD history had to be less than 14 days, and exclusion criteria were rupture, impending rupture, malperfusion. Of the 61 patients randomised, 80% were DeBakey type IIIB. RESULTS Thirty-one patients were randomised to the BMT group and 30 to the BMT+TAG group. Mean age was 63 years for both groups. The left subclavian artery was completely covered in 47% and in part in 17% of the cases. During the first 30 days, no deaths occurred in either group, but there were three crossovers from the BMT to the BMT+TAG group, all due to progression of disease within 1 week. There were two withdrawals from the BMT+TAG group. At the 1-year follow up there had been another two failures in the BMT group: one malperfusion and one aneurysm formation (p = .056 for all). One death occurred in the BMT+TAG group. For the overall endpoint BMT+TAG was significantly different from BMT only (p < .001). Incomplete false lumen thrombosis, was found in 13 (43%) of the TAG+BMT group and 30 (97%) of the BMT group (p < .001). The false lumen reduced in size in the BMT+TAG group (p < .001) whereas in the BMT group it increased. The true lumen increased in the BMT+TAG (p < .001) whereas in the BMT group it remained unchanged. The overall transverse diameter was the same at the beginning and after 1 year in the BMT group (42.1 mm), but in the BMT+TAG it decreased (38.8 mm; p = .062). CONCLUSIONS Uncomplicated AD can be safely treated with the Gore TAG device. Remodelling with thrombosis of the false lumen and reduction of its diameter is induced by the stent graft, but long term results are needed.

Importance of false lumen thrombosis in type B aortic dissection prognosis

BACKGROUND Partial thrombosis of the false lumen has been reported as a significant predictor of mortality during follow-up in patients with acute type B aortic dissection. The purpose of this study was to investigate the correlation of false lumen thrombosis and aortic expansion during follow-up in patients with acute type B aortic dissection. METHODS All medically treated patients with acute type B aortic dissection observed in 4 cardiovascular referral centers between 1998 and 2011, with admission and follow-up computed tomography or magnetic resonance imaging scans, were included. Aortic diameters of the dissected aortas were measured at 4 levels on the baseline and follow-up scans, and annual growth rates were calculated. Univariate and multivariate regression analyses were used to investigate the effect of false lumen thrombosis on aortic growth rate. RESULTS A total of 84 patients were included, of whom 40 (47.6%) had a partially thrombosed false lumen, 7 (8.3%) had a completely thrombosed false lumen, and 37 (44.0%) had a patent false lumen. A total of 273 of the 336 (81.3%) evaluated aortic levels were dissected segments. Overall, the mean aortic diameter increased significantly at all evaluated levels (P < .001). Univariate analysis showed that annual aortic growth rates were significantly higher in those segments having a false lumen with partial thrombosis (mean, 4.25 ± 10.2) when compared with the patent group (mean, 2.10 ± 5.56; P = .035). In multivariate analysis, partial lumen thrombosis was an independent predictor of higher aortic growth (adjusted mean difference, 2.05 mm/year; 95% confidence interval, 0.10-4.01; P = .040). CONCLUSIONS In patients with acute type B aortic dissection, aortic segments with a partially thrombosed false lumen have a significantly higher annual aortic growth rate when compared with those presenting with patent or complete thrombosis of the false lumen. Therefore, patients with partial thrombosis require more intensive follow-up and may benefit from prophylactic intervention.

Open surgery versus endovascular repair of ruptured thoracic aortic aneurysms.

BACKGROUND Ruptured descending thoracic aortic aneurysm (rDTAA) is a cardiovascular catastrophe, associated with high morbidity and mortality, which can be managed either by open surgery or thoracic endovascular aortic repair (TEVAR). The purpose of this study is to retrospectively compare the mortality, stroke, and paraplegia rates after open surgery and TEVAR for the management of rDTAA. METHODS Patients with rDTAA treated with TEVAR or open surgery between 1995 and 2010 at seven institutions were identified and included for analysis. The outcomes between both treatment groups were compared; the primary end point of the study was a composite end point of death, permanent paraplegia, and/or stroke within 30 days after the intervention. Multivariate logistic regression analysis was used to identify risk factors for the primary end point. RESULTS A total of 161 patients with rDTAA were included, of which 92 were treated with TEVAR and 69 with open surgery. The composite outcome of death, stroke, or permanent paraplegia occurred in 36.2% of the open repair group, compared with 21.7% of the TEVAR group (odds ratio [OR], 0.49; 95% confidence interval [CI], .24-.97; P = .044). The 30-day mortality was 24.6% after open surgery compared with 17.4% after TEVAR (OR, 0.64; 95% CI, .30-1.39; P = .260). Risk factors for the composite end point of death, permanent paraplegia, and/or stroke in multivariate analysis were increasing age (OR, 1.04; 95% CI, 1.01-1.08; P = .036) and hypovolemic shock (OR, 2.47; 95% CI, 1.09-5.60; P = .030), while TEVAR was associated with a significantly lower risk of the composite end point (OR, 0.44; 95% CI, .20-.95; P = .039). The aneurysm-related survival of patients treated with open repair was 64.3% at 4 years, compared with 75.2% for patients treated with TEVAR (P = .191). CONCLUSIONS Endovascular repair of rDTAA is associated with a lower risk of a composite of death, stroke, and paraplegia, compared with traditional open surgery. In rDTAA patients, endovascular management appears the preferred treatment when this method is feasible.

Aortic expansion after acute type B aortic dissection.

BACKGROUND A considerable number of patients with acute type B aortic dissection (ABAD) treated with medical management alone will exhibit aortic enlargement during follow-up, which could lead to aortic aneurysm and rupture. The purpose of this study was to investigate predictors of aortic expansion among ABAD patients enrolled in the International Registry of Acute Aortic Dissection. METHODS We analyzed 191 ABAD patients treated with medical therapy alone enrolled in the registry between 1996 and 2010, with available descending aortic diameter measurements at admission and during follow-up. The annual aortic expansion rate was calculated for all patients, and multivariate regression analysis was used to investigate factors affecting the expansion rate. RESULTS Aortic expansion was observed in 59% of ABAD patients; mean expansion rate was 1.7±7 mm/y. In multivariate analysis, white race (regression coefficient [RC], 4.6; 95% confidence interval [CI], 1.4 to 7.7) and an initial aortic diameter less than 4.0 cm (RC, 6.3; 95% CI, 4.0 to 8.6) were associated with increased aortic expansion. Female sex (RC, -3.8; 95% CI, -6.1 to -1.4), intramural hematoma (RC, -3.8; 95% CI, -6.5 to -1.1), and use of calcium-channel blockers (RC, -3.8; 95% CI, -6.2 to -1.3) were associated with decreased aortic expansion. CONCLUSIONS White race and a small initial aortic diameter were associated with increased aortic expansion during follow-up, and decreased aortic expansion was observed among women, patients with intramural hematoma, and those on calcium-channel blockers. These data raise the possibility that the use of calcium-channel blockers after ABAD may reduce the rate of aortic expansion, and therefore further investigation is warranted.

Predictors of aortic growth in uncomplicated type B aortic dissection

BACKGROUND Patients with uncomplicated acute type B aortic dissection (ABAD) generally can be treated with conservative medical management. However, these patients may develop aortic enlargement during follow-up, with the risk for rupture, which necessitates intervention. Several predictors have been studied in recent years to identify ABAD patients at high risk for aortic enlargement who may benefit from early surgical or endovascular intervention. This study systematically reviewed and summarized the current available literature on prognostic variables related to aortic enlargement during follow-up in uncomplicated ABAD patients. METHODS Studies were included if they reported predictors of aortic growth in uncomplicated ABAD patients. Studies about type A aortic dissection, aortic aneurysm, intramural hematoma, or ABAD that required acute intervention were excluded. RESULTS A total of 18 full-text articles were selected. The following predictors of aortic growth in ABAD patients were identified: age <60 years, white race, Marfan syndrome, high fibrinogen-fibrin degradation product level (≥20 μg/mL) at admission, aortic diameter ≥40 mm on initial imaging, proximal descending thoracic aorta false lumen (FL) diameter ≥22 mm, elliptic formation of the true lumen, patent FL, partially thrombosed FL, saccular formation of the FL, presence of one entry tear, large entry tear (≥10 mm) located in the proximal part of the dissection, FL located at the inner aortic curvature, fusiform dilated proximal descending aorta, and areas with ulcer-like projections. Tight heart rate control (<60 beats/min), use of calcium-channel blockers, thrombosed FL, two or more entry tears, FL located at the outer aortic curvature, and circular configuration of the true lumen were associated with negative or limited aortic growth. CONCLUSIONS Several predictors might be used to identify those ABAD patients at high risk for aortic growth. Although conservative management remains indicated in uncomplicated ABAD, these patients might benefit from closer follow-up or early endovascular intervention.

Plasma levels of metalloproteinases-9 and -2 in the acute and subacute phases of type A and type B aortic dissection.

Objectives Aortic dissection is characterized by an acute phase of medial dissection and a subacute-chronic phase of vessel wall repair. Matrix metalloproteinases (MMPs), through degradation of extracellular matrix, may play an important role in these processes. Elevation of MMPs might represent an opportunity to diagnostically characterize acute or chronic aortic processes. We examined the potential diagnostic role of MMP-9 and MMP-2 in different phases of aortic dissection. Methods Plasma levels of MMPs were evaluated by enzyme-linked immunosorbent assay technique in 13 patients affected by acute aortic dissection (nine type A, four type B). Ten healthy subjects were used as controls. In patients with type B aortic dissection treated medically, plasma curves (1, 3, 6, 12, 24, 48 and 96 h; 1 and 2 weeks; and 2 months from symptom onset) were also assessed. Aortic tissue samples obtained during surgery were evaluated by immunohistochemistry and western blot for MM-9 and tissue inhibitor of metalloproteinase-1 expression. Results MMP-9 plasma levels were increased in patients affected by type A and type B aortic dissection presenting within 1 h from onset of symptoms compared to controls (29.3 ± 16.1 and 16.7 ± 2.1 ng/ml versus 7.74 ± 1.6 ng/ml, P < 0.03, respectively). No differences were detected in MMP-2 plasma levels compared to controls (4.84 ± 1.2 ng/ml for type A and 6.16 ± 0.6 ng/ml versus 3.17 ± 1.0 ng/ml for controls, P = NS, respectively). In type B aortic dissection, mean MMP-9 plasma levels increased significantly from hospital admission to 2-month follow-up (16.7 ± 2.1 ng/ml versus 58.0 ± 8.2 ng/ml, P < 0.0001). Conversely, no difference in MMP-2 plasma levels was evident during follow-up (6.16 ± 0.6 ng/ml versus 4.28 ± 0.4 ng/ml, P = NS, respectively). Low-moderate (+/++) expression of MMP-9 was evident at immunohistochemistry in the acute phase whereas a marked expression (++++) was detected in the subacute phase. Conclusions This pilot study suggests that the acute and subacute phase of both type A and type B aortic dissection is characterized by an increase of MMP-9 plasma levels. A marked increase is also evident in the subacute phase of medically treated type B aortic dissection as an expression of aortic wall remodelling. An increase of proteolytic activity could accompany attempts of the dissected aorta to heal itself but such a phenomena might further weaken the aortic wall, predisposing it to dilation and/or rupture.