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Felipe Navarro

Publications and source records attributed to Felipe Navarro.

9 recordsLinked to original sources
PubMed2004

[Tako-tsubo syndrome associated with a long course of the left anterior descending coronary artery along the apical diaphragmatic surface of the left ventricle].

INTRODUCTION AND OBJECTIVES: Tako-tsubo-like transient left ventricular apical ballooning has been described in Japan, but few cases have been reported in Western countries. We report one of the first series outside Japan, which provides new information on the coronary anatomy of this disorder. PATIENTS AND METHODS: From January 1998 to February 2003 we observed 11 patients with a clinical suspicion of acute myocardial infarction, normal coronary arteries, and transient tako-tsubo-like systolic left ventricular apical ballooning. We compared the coronary artery anatomy in these 11 patients with that in 44 controls matched for age and sex: 22 with normal coronary arteries and 22 with acute myocardial infarction related with an obstructive thrombus in the left anterior descending coronary artery. RESULTS: As in Japanese patients, tako-tsubo syndrome in Caucasian patients frequently occurs in women in their seventh or eighth decades of life, and is usually preceded by emotional or physical stress. The left anterior descending in our patients with tako-tsubo syndrome was longer overall, and its recurrent diaphragmatic segment was longer, than in controls. To compare these groups we designed a measure termed recurrent segment index (left anterior descending recurrent segment length/total left anterior descending length x 100). In tako-tsubo syndrome this index was 22.3 (1.5)%, vs 10.9 (6.7)% in normal controls (P<.001), and 11.3 (7.7)% in acute myocardial infarction patients (P<.001). Patients with acute myocardial infarction and a high recurrent segment index (> or =16%) had ventriculographic findings of systolic apical ballooning identical to those in patients with tako-tsubo syndrome. CONCLUSIONS: All our patients with tako-tsubo syndrome had a left anterior descending with a long recurrent segment. The identical ventriculographic findings in patients with tako-tsubo syndrome and those with acute myocardial infarction with a long recurrent segment may be due to a common etiology.

Adult↗
PubMed2003

Endothelin-1 induced proinflammatory markers in the myocardium and leukocytes of guinea-pigs: role of glycoprotein IIB/IIIA receptors.

AIM: To assess whether endothelin-1 (ET-1) induces the in vivo expression of inflammatory-related proteins, namely cyclooxygenase-2 (COX-2) and tissue factor, in the myocardium and circulating leukocytes of guinea-pigs. The involvement of platelets was also analyzed. METHODS: ET-1 (0.013 microg/min) was infused to male guinea-pigs for 45 min in the presence and absence of tirofiban, a nonpeptidic blocker of the glycoprotein IIb/IIIa receptor (GPIIb/IIIa). Tissue factor and COX-2 expression were determined by Western blot. RESULTS: No changes in mean arterial pressure and heart rate were detected. ET-1-infused guinea-pigs showed a marked increase in the number of platelets expressing activated GPIIb/IIIa receptors (0.8+/-0.03% vs. 6.5+/-0.2%; P<0.05). Tirofiban (10 microg/Kg bw/min) blunted ex vivo platelet aggregation in response to ADP, although only partially reduced COX-2 and tissue factor expression in both the myocardium and leukocytes of ET-1-infused guinea-pigs. The myocardium of platelet-depleted guinea-pigs also showed a reduced COX-2 expression after ET-1 infusion (57+/-3% reduction; P<0.05). In vitro studies demonstrated that platelets (10(7) and 10(9) platelets/well) enhanced ET-1 (10(-7) mol/l)-induced COX-2 expression in heart slices. CONCLUSION: ET-1 stimulated in vivo the expression of the pro-inflammatory proteins COX-2 and tissue factor in the myocardium and in leukocytes by a mechanism GPIIb/IIIa platelet receptors.

Animals↗
PubMed2003

Young patients with iliofemoral deep venous thrombosis should receive thrombolytic therapy.

A 20-year-old otherwise healthy woman on oral contraceptive pills presents with sudden-onset left leg swelling and pain extending from her calf to her groin. Pulmonary embolism symptoms are lacking. Venous duplex ultrasound reveals acute deep venous thrombosis (DVT) involving the distal external iliac, common femoral, superficial femoral, and popliteal veins. Her leg is markedly swollen, slightly cool to the touch, but has preserved pedal pulses. She is unable to ambulate secondary to pain. Thrombolytic therapy to eliminate the DVT is recommended.

Adult↗
PubMed2002

Ultrasonic characterization of the pulmonary venous wall: echographic and histological correlation.

BACKGROUND: Pulmonary vein isolation with radiofrequency catheter ablation techniques is used to prevent recurrences of human atrial fibrillation. Visualization of the architecture at the venoatrial junction could be crucial for these ablative techniques. Our study assesses the potential for intravascular ultrasound to provide this information. METHODS AND RESULTS: We retrieved 32 pulmonary veins from 8 patients dying from noncardiac causes. We obtained cross-sectional intravascular ultrasound (IVUS) images with a 3.2F, 30-MHz ultrasound catheter at intervals on each vein. Histological cross-sections at the intervals allowed comparisons with ultrasonic images. The pulmonary venous wall at the venoatrial junction revealed a 3-layered ultrasonic pattern. The inner echogenic layer represents both endothelium and connective tissue of the media (mean maximal thickness, 1.4+/-0.3 mm). The middle hypoechogenic stratum corresponds to the sleeves of left atrial myocardium surrounding the external aspect of the venous media. This layer was thickest at the venoatrial junction (mean maximal thickness, 2.6+/-0.8 mm) and decreased toward the lung hilum. The outer echodense layer corresponds to fibro-fatty adventitial tissue (mean maximal thickness, 2.15+/-0.36 mm). We found a close agreement among the IVUS and histological measurements for maximal luminal diameter (mean difference, -0.12+/-1.3 mm) and maximal muscular thickness (mean difference, 0.17+/-0.13 mm) using the Bland and Altman method. CONCLUSIONS: Our experimental study demonstrates for the first time that IVUS images of the pulmonary veins can provide information on the distal limits and thickness of the myocardial sleeves and can be a valuable tool to help accurate targeting during ablative procedures.

Adult↗