Dilatación de la raíz aórtica en pacientes con válvula bicúspide tras la sustitución valvular aórtica / Dilatation of the aortic root in patients with bicuspid valve after aortic valve replacement

Introducción y objetivos: La válvula aórtica bicúspide (VAB) esta vinculada con la patología aórtica.Pacientes con VAB tienen elevada probabilidad de requerir cirugía debido a dilatación aórtica o afectaciónvalvular. La progresión en la dilatación aortica luego de la sustitución de la válvula aórtica (SVA), no se haevaluado forma definitoria. Métodos: Un total de 23 pacientes con VAB y diámetro de la raíz aortica inferior a45 mm fueron seguidos durante una media de 8 años luego de la SVA. La medición ecocardiográfica de laraíz aórtica y la aorta tubular se realizó a los 6 y 8 años de la cirugía. Se determinaron predictores dedilatación. Resultados: La raíz aórtica entre 6 (34,6 ± 7,4 mm) y 8 años (37,6 ± 7,7 mm) de seguimientoincrementó significativamente (p <0,023), no se encontraron diferencias con la aorta tubular. La dilatación seobservó principalmente entre fumadores, con antecedentes familiares y dislipémia. Los factores predictorespara dilatación de la raíz aórtica fueron: antecedentes familiares de VAB o patología aórtica, tamaño de laprótesis y superficie corporal (SC). El análisis de regresión multivariado evidenció solo la SC y antecedentesfamiliares como predictores significativos. Conclusión: La raíz aórtica continúa dilatándose tras la SVA enpacientes con VAB. La SC y la historia familiar de patología aórtica, son fuertes predictores de dilatación de laraíz aórtica. Estos pacientes deben ser seguidos de cerca luego de la SVA.

Background: Bicuspid aortic valve (BAV) has been closely correlated with aortic pathology. BAV patientshave a high probability of being operated along their lifetime for aortic disease. Progression of aortic dilatationafter aortic valve replacement (AVR) has not being definitely assessed. Methods: A total of 23 BAV withaortic diameter ≤ 45mm patients were followed for a mean of 8 years after AVR. Echocardiographicmeasurement of the aortic root and tubular aorta was done after a mean of 6 and 8 years post-operatively.Predictors for dilatation were estimated. Results: Paired comparison of aortic root diameter between 6(34.6±7.4 mm) and 8 years (37.6±7.7 mm) of follow-up showed that its dimension increased significantly(p<0.023) while no differences were found with the tubular aorta. Dilatation was seen mainly in smokers,family history and dyslipemic patients. Univariate predictors for aortic root dilatation were: family history ofBAV or aortic pathology, prosthesis size and body surface area (BSA). Multivariate regression evidenced onlyBSA (beta coefficient 11.5) and family history (beta coefficient 4.5) as significant predictors. Conclusion:Aortic root continues to dilate after AVR in BAV patients. Higher BSA and family history of aortic pathologywere found as strong predictors of aortic root dilatation. These patients should be closely followed after AVR.

Dilatación de la raíz aórtica en pacientes con válvula bicúspide tras la sustitución valvular aórtica / Aortic root dilatation in patients with Bicuspid aortic valve late after aortic valve replacement

Introducción: La válvula aórtica bicúspide (VAB) está vinculada con la patología aórtica. Pacientes con VAB tienen elevada probabilidad de requerir cirugía debido a dilatación aórtica o afectación valvular. La progresión en la dilatación aortica luego de la sustitución de la válvula aórtica (SVA) no se ha evaluado en forma definitoria. Métodos: Un total de 23 pacientes con VAB y diámetro de la raíz aortica inferior a 45 mm fueron seguidos durante una media de 8 años luego de la SVA. La medición ecocardiográfica de la raíz aórtica y la aorta tubular se realizó a los 6 y 8 años de la cirugía. Se determinaron predictores de dilatación. Resultados: La raíz aórtica entre 6 y 8 años de seguimiento incrementó significativamente de 34,6 +/- 7,4 a 37,6 +/- 7,7 mm (p <0,023), mientras que no se encontraron diferencias con la aorta tubular. La dilatación se observa principalmente en los fumadores, aquellos con antecedentes familiares y en los pacientes dislipémicos. Los factores predictores para dilatación de la raíz aórtica fueron: antecedentes familiares de VAB o de patología aórtica, el tamaño de la prótesis y la superficie corporal (SC). El análisis de regresión multivariado evidenció solo la SC y antecedentes familiares como predictores significativos de dilatación. Conclusión: La raíz aórtica continúa dilatándose tras la SVA en pacientes con VAB. La SC y la historia familiar de patología aórtica son fuertes predictores de dilatación de la raíz aórtica. Estos pacientes deben ser seguidos de cerca luego de la SVA.

Background: The presence of a bicuspid aorotic valve (BAV) is associated to aortic disease. Along their lifetime, BAV patients are highly likely to require surgery. Progression of aortic dilatation after aortic valve replacement (AVR) has not been definitely assessed. Methods: A total of 23 BAV patients with aortic diameter < 45mm were followed for a mean of 8 years after AVR. The aortic root and proximal ascending aorta were measured by echocardiografy 6 and again 8 years after surgery. Predictors for dilatation were estimated based on demographic data and pharmacologic treatment. Results: The aortic root diameter increased from 34.6+/-7.4 to 37.6+/-7.7 mm at 6 and 8 years post surgery, respectively (p=0.023). No change was observed at the tubular aorta . Mean progression of aortic root and tubular aorta during the 2-year interval was 2.9+/-4.7 mm and 0.4+/-5.8 mm respectively. Dilatation was seen mainly in smokers, those with a family history or dyslipidemia. Univariate predictors for aortic root dilatation were: family history of BAV or aortic pathology, prosthesis size and body surface area (BSA). Multivariate regression evidenced only BSA (beta coefficient 11.5) and family history (beta coefficient 4.5) as significant predictors. Conclusion: Aortic root continues to dilate after AVR in BAV patients. Higher BSA and family history of aortic pathology were found to be strong predictors of aortic root dilatation. These patients should be closely followed after AVR.

Risk of subsequent aortic dilatation is low in patients with bicuspid aortic valve and normal aortic root diameter at the time of aortic valve replacement.

Bicuspid aortic valves (BAVs) are associated with ascending aortic aneurysms. We studied BAV patients before and after aortic valve replacement (AVR) to determine the risk and predictors of aortic root dilatation after surgery. BAV patients (n=60) with an aortic root

Superoxide-mediated inactivation of nitric oxide and peroxynitrite formation by tobacco smoke in vascular endothelium: studies in cultured cells and smokers.

Tobacco smoke is known to cause nitric oxide ((*)NO) inactivation and endothelial dysfunction. In this work we evaluated the interplay between (.)NO and superoxide (O(2)(*-)) radicals and the consequent impact on (*)NO bioavailability and nitroxidative stress in bovine aortic endothelial cells exposed to cigarette smoke extract (CSE) and in smokers. Bovine aortic endothelial cells in the presence of CSE triggered O(2)(*-) production as indicated by spin-trapping electron paramagnetic resonance experiments. O(2)(*-) was produced both extracellulary (3.4 vs. 1.0 nmol.h(-1)*mg(-1); CSE vs. control; cytochrome c(3+) reduction assay) and intracellularly (40% inhibition of cytosolic aconitase). CSE also led to the production of peroxynitrite as evaluated by dihydrorhodamine oxidation and protein tyrosine nitration on cells. O(2)(*-) and peroxynitrite formation were decreased by ascorbate and alpha-tocopherol. Additionally, CSE led to the oxidation of endothelial nitric oxide synthase increasing the monomeric inactive form of endothelial nitric oxide synthase. Smokers and age-matched healthy volunteers were supplemented orally with 500 mg ascorbate plus 400 IU all-rac-alpha-tocopherol every 12 h for 165 days. Smokers had endothelial dysfunction compared with control subjects (95% confidence interval: 2.5, 8.3 vs. 10.6, 14.2; P < 0.05) as assessed by flow-mediated dilation of the brachial artery, and plasma levels of protein 3-nitrotyrosine were 1.4-fold higher. The loss of flow-mediated dilation in smokers reverted after a long-term antioxidant supplementation (95% confidence interval: 13.9, 19.9; P < 0.05), reaching values comparable with the control population. Our data indicate that elements on tobacco smoke, most likely through redox cycling, divert (*)NO toward peroxynitrite by inducing O(2)(*-) production in vascular endothelial cells both in vitro and in vivo.

Pulmonary artery dissection: echocardiographic findings and diagnosis.

Pulmonary artery dissection is a rare but life-threatening event, predisposing to sudden cardiac death or cardiogenic shock. It is often associated with underlying congenital disorders predisposing to pulmonary hypertension. Rarely, it is diagnosed by echocardiography or other image techniques. We present a case report of a pulmonary artery dissection, diagnosed primarily by echocardiography. The patient died soon after refusing any interventional approach after a short period under medication.