Paradoxical increase in ambulatory SBP in coarctation of aorta a compared to essential hypertension.

BACKGROUND: The relationship between office vs. ambulatory blood pressure (BP) indices are well-studied in patients with essential hypertension and based on these data, it is known that the average 24-h ambulatory BP is typically lower than office BP. However, emerging data show that office SBP underestimates arterial afterload in patients with coarctation of aorta (COA), and a minimal increase in stroke volume during low-intensity exercise results in an exaggerated rise in SBP as compared to those with essential hypertension. We hypothesized that COA patients will have higher ambulatory SBP and a higher prevalence of masked hypertension compared to patients with essential hypertension. METHODS: Case-control study of 118 COA patients and 118 patients with essential hypertension matched by age, sex, BMI and office SBP. RESULTS: Although both groups had similar office SBP (132 ± 17 mmHg) by design, the COA group had paradoxical increases in 24-h ambulatory SBP (135 ± 14 vs. 126 ± 13; P < 0.001) and daytime ambulatory SBP (142 ± 16 vs. 130 ± 13; P < 0.001), and less nocturnal dipping (-3 ± 5 vs. -9 ± 4; P < 0.001). The COA group also had a higher prevalence of masked hypertension [36 (31%) vs 14 (12%); P < 0.001), and worse arterial function indices. CONCLUSION: These findings underscore the potential limitations of relying on office SBP for screening/monitoring of hypertension in COA and potential pitfalls in extrapolating essential hypertension guidelines recommendations to the treatment of COA. It also provides the rationale for further studies to determine if pharmacologic BP interventions guided by ambulatory BP data will improve clinical outcomes in the COA population.

Parvovirus Infection and Thrombotic Thrombocytopenic Purpura in an Adult Patient With Sickle Cell Beta-Thalassemia.

Parvovirus infection and thrombotic thrombocytopenic purpura (TTP) are rare manifestations in adults with sickle cell beta-thalassemia. Due to the lack of a clear demarcation between the complications related to sickle cell disease (SCD) and TTP, the diagnosis is often challenging. The treatment requirements for both these entities are divergent and complicated, thus necessitating a careful plan of action during atypical presentations. Here we present a case of a 22-year-old woman during the peripartum period with fever, generalized body aches, and large joint pains that soon evolved into labor. The patient's history was suggestive of an undiagnosed and inherited blood disorder. The presentation of aplastic crisis-splenic sequestration during early adulthood is atypical for the SCD course in general populations. Moreover, as the patient's clinical status deteriorated with blood transfusion, the diagnosis and management of a sickle cell crisis event and TTP added to the dilemma in the presence of non-classic parvovirus infection. Though the causation of TTP due to SCD-parvovirus infection is questionable, the treatment of the baseline sickle cell crisis with the novel supportive measures resolved the underlying complications in our patient, suggesting the causal effect. As a result of this, we emphasize the importance of being vigilant about such atypical presentations to avoid delays in diagnosis and treatment of such life-threatening emergencies like TTP.

Effect of Combined Ventricular-Arterial Stiffening on Exercise Hemodynamics in Adults With Repaired Coarctation of Aorta.

BACKGROUND: Patients with coarctation of aorta (COA) have arterial stiffening, and this is associated with impaired cardiac reserve and hypertensive systolic blood pressure (SBP) response during exercise. However, whether patients with COA have concomitant left ventricular (LV) stiffening and the potential impact of combined ventricular-arterial stiffening on exercise hemodynamics are unknown. METHODS: We studied 174 patients with repaired COA (aged 39 ± 11 years and male 103 [59%]) and 174 matched controls. Our study hypotheses are: (1) patients with COA have higher ventricular-arterial stiffness (end-systolic elastance [Ees] and arterial elastance [Ea]) as compared with controls; (2) ventricular-arterial stiffness was associated with LV stroke volume augmentation (ΔLVSV) and SBP augmentation (ΔSBP) during exercise among patients with COA. RESULTS: Despite similar systolic SBP, patients with COA had higher Ea (1.8 ± 0.4 vs 1.4 ± 0.4 mm Hg/mL, P < 0.001), higher Ees (2.41 ± 0.65 vs 2.17 ± 0.40 mm Hg/mL, P < 0.001), but similar Ea/Ees (0.87 ± 0.29 vs 0.83 ± 0.33, P = 0.2). ΔLVSV was 6.1 ± 1.4 mL/beat. Combined ventricular-arterial stiffness had a stronger correlation with ΔLVSV as compared with Ea alone (r = -0.53 vs r = -0.41, P = 0.006) and as compared with Ees alone (r = -0.53 vs r = -0.46, P = 0.02). ΔSBP was 48 ± 21 mm Hg. Combined ventricular-arterial stiffness had a stronger correlation with ΔSBP as compared with Ea alone (r = 0.57 vs r = 0.43, P < 0.001) and as compared with Ees alone (r = 0.57 vs r = -0.39, P < 0.001). CONCLUSION: Patients with COA had combined ventricular-arterial stiffening, and this was associated with impaired cardiac reserve and hypertensive SBP response during exercise. These findings provide foundation for further studies to determine whether drugs that reduce both ventricular and arterial stiffness will improve exercise capacity and hemodynamics in this unique population.

CONTEXTE: La coarctation de l'aorte (CA) s'accompagne d'une rigidification des artères, qui est à son tour associée à une altération de la réserve de force du cœur et à une augmentation de la pression artérielle systolique (PAS) à l'effort. On ne sait toutefois pas si la CA entraîne aussi une rigidification du ventricule gauche, et on ne connaît pas les répercussions possibles d'une rigidification ventriculaire et artérielle sur les paramètres hémodynamiques à l'effort. MÉTHODOLOGIE: Nous avons étudié 174 patients présentant une CA corrigée (âge : 39 ± 11 ans; hommes : 103 [59 %]) et 174 témoins appariés. Nos hypothèses étaient les suivantes : 1) la rigidité ventriculaire et artérielle (élastance télésystolique [ETS] et élastance artérielle [EA]) est plus importante chez les sujets présentant une CA que chez les sujets témoins; 2) la rigidité ventriculaire et artérielle est associée à une augmentation du volume d'éjection ventriculaire gauche (ΔVEVG) et à une augmentation de la pression artérielle systolique (ΔPAS) à l'effort chez les patients présentant une CA. RÉSULTATS: Malgré une PAS comparable, les patients présentant une CA avaient une EA plus élevée que les sujets témoins (1,8 ± 0,4 vs 1,4 ± 0,4 mmHg/ml, p < 0,001) et une ETS également plus élevée (2,41 ± 0,65 vs 2,17 ± 0,40 mmHg/ml, p < 0,001), mais un rapport EA/ETS similaire (0,87 ± 0,29 vs 0,83 ± 0,33, p = 0,2). La ΔVEVG était de 6,1 ± 1,4 ml/battement. La rigidité ventriculaire et artérielle mixte était plus fortement corrélée avec une ΔVEVG, comparativement à l'EA seule (r = -0,53 vs r = -0,41, p = 0,006) et à l'ETS seule (r = -0,53 vs r = -0,46, p = 0,02). La ΔPAS était de 48 ± 21 mmHg. La rigidité ventriculaire et artérielle mixte était plus fortement corrélée avec la ΔPAS, comparativement à l'EA seule (r = 0,57 vs r = 0,43, p < 0,001) et à l'ETS seule (r = 0,57 vs r = -0,39, p < 0,001). CONCLUSION: La CA s'accompagnait d'une rigidification ventriculaire et artérielle, elle-même associée à une altération de la réserve de force du cœur et à une augmentation de la PAS à l'effort. Ces résultats pourront servir de fondements à des études complémentaires visant à déterminer si un traitement qui réduit la rigidité ventriculaire et artérielle pourrait améliorer la capacité à l'effort et les paramètres hémodynamiques dans cette population particulière.