The Impact of Pre-existing Blood Pressure Control in Patients With Acute Aortic Dissections

Abstract

Arterial hypertension (HTN) is considered a seminal risk factor for aortic dissection (AD). The impact of chronic HTN control on the location, extent, and early outcome of acute AD has not been evaluated. The purpose of this study was to evaluate whether pre-existing blood pressure (BP) control lessens the extent of dissection and has a favorable impact on outcome of patients with acute AD. Consecutive patients admitted from 2011 to 2019 who had a most recent BP recorded within a mean of 4 ± 3 months before the AD were retrospectively analyzed. HTN was defined as normal (BP <140/90 mm Hg), stage 1 (BP >140/90 mm Hg and <160/100 mm Hg), or stage 2 or higher (BP >160/100 mm Hg). The number of hypertensive medications (MEDs) was used as a surrogate marker of HTN severity. There were 92 patients (57% men, 43% women; mean age, 64 ± 15 years) with acute AD (63% Stanford type A, 37% Stanford type B). Forty-eight (52%) patients had normal BP, including 16 patients with no history of HTN and taking no MEDs. Forty-four (48%) patients had elevated BP, including 26 (28%) with stage 1 HTN and 18 (19%) with stage 2 HTN. Compared with patients with normal BP, those with stage 1 and stage 2 HTN were younger (70 ± 13 years vs 58 ± 13 years; P < .001), but there were no differences in other demographics, risk factors, comorbidities, or prior aneurysms. Type A dissections occurred in 32 (67%) patients with normal BP, which was not significantly different compared with 16 (61%) stage 1 HTN patients or 10 (55%) stage 2 HTN patients. There were no group differences in the distal extent of the dissections, mean length of hospital stay, final discharge status, or 30-day mortality. Compared with before AD, all three groups had a higher mean number of MEDs to achieve normal BP at discharge that persisted at a mean follow-up of 18 ± 14 months (P < .001; Fig). Half of patients with acute AD have well-controlled HTN or no antecedent history of HTN. The degree of pre-existing HTN control had no bearing on the type or extent of AD, length of stay, or early outcome. Regardless of the state of HTN control before AD, the consistent and sustained increase in the severity of HTN after AD suggests that the dissection process has a profound and lasting effect on BP regulation. Further studies are indicated to elucidate the pathologic mechanisms involved in AD.