PubMed Health⌕ Search

Biomedical subjects

C E Ruiz

Publications and source records attributed to C E Ruiz.

54 records · Page 3Linked to original sources
PubMed1992

Stenting of the arterial duct: a new approach to palliation for pulmonary atresia.

OBJECTIVE: To assess the possibility of maintaining ductal patency in neonates with complex pulmonary atresia by percutaneous implantation of balloon expandable stents. PATIENTS: Two duct-dependent neonates with long segment pulmonary atresia, right sided aortic arch, and left sided arterial duct. RESULTS: Stents with final diameter of 3.5 or 4 mm and initial length of 7 or 15 mm were successfully positioned in the arterial duct. Two stents were required in one child and four in the other in order to stent the entire length of the duct. After the procedures the ducts remained widely patent and arterial oxygen saturations remained above 80%. Complications of the procedures included perforation of a peripheral pulmonary artery and cardiac perforation, both caused by guide wire manipulation. Both babies died suddenly, one at five weeks, and the other at nine days after successful stenting of the duct. Both ducts were patent at necropsy; the exact cause of one death was not clearly defined, but the second seemed to be caused by pneumococcal septicaemia. CONCLUSIONS: Stenting of the arterial duct is technically feasible. It provides adequate palliation for neonates with pulmonary atresia at least in the short term and it seems to result in balanced, central perfusion of both pulmonary arteries. This preliminary report suggests that this previously untried technique may prove to be a promising and attractive alternative to neonatal aortopulmonary shunt operation.

Dinoprostone↗
PubMed1991

Stunned left ventricular myocardium after exercise treadmill testing in coronary artery disease.

Myocardial stunning (postischemic ventricular dysfunction) occurs in dogs after coronary stenosis following treadmill exercise. Less data are available in humans regarding development of stunned myocardium after exercise. Regional wall motion changes were evaluated in 22 patients with known coronary artery disease using 2-dimensional echocardiography and exercise treadmill testing. Wall motion was scored as 1 = normal, 2 = hypokinetic, 3 = akinetic, 4 = dyskinetic. At least 1 left ventricular segment with normal resting function developed an increase in wall motion score at 15 or 30 minutes compared with values at rest. The wall motion score in the midportion of the ventricular septum increased from 1.0 at rest to 1.6 (p less than 0.004) at 30 minutes after exercise; the basal inferior wall score worsened from 1.0 at rest to 1.9 (p less than 0.01) at 30 minutes after exercise. Coronary angiographic data in these patients revealed that left anterior descending narrowing correlated best with left ventricular septal wall motion abnormalities, whereas right coronary artery and circumflex narrowing best correlated with inferior and posterior wall motion abnormalities. Eight normal adult volunteers with no history of myocardial ischemia also underwent 2-dimensional echocardiography and exercise testing. No wall motion abnormalities were observed at any time after exercise. The present study suggests that in patients with coronary artery disease, exercise treadmill testing may induce regional wall motion abnormalities of the left ventricle that persist greater than or equal to 30 minutes after exercise, an observation consistent with the phenomenon of stunned myocardium.

Adult↗
PubMed1991

Congenital atresia of left main coronary artery: proposed mechanism for severe disabling angina in a patient with non-atherosclerotic single right coronary artery--a case report.

A patient with progressive disabling angina was found to have a single right coronary artery with atresia of the left main coronary artery, and absence of any obstructive coronary disease. The patient required aortocoronary by-pass surgical reconstruction of a left main coronary artery to control her angina. Possible mechanisms for the development of her anginal pain are briefly discussed.

Angina Pectoris↗
PubMed1990

Percutaneous double balloon valvotomy for severe rheumatic mitral stenosis.

Percutaneous double balloon valvotomy for severe rheumatic mitral stenosis was successfully performed in 281 of 285 consecutive patients. The changes evoked were a decrease of the mean transvalvular gradient from 16 +/- 7 to 5 +/- 3 mm Hg, an increase in cardiac output from 3.8 +/- 1.0 liters/min to 5.4 +/- 1.5 liters/min and an increase in mitral valve area from 0.86 +/- 0.24 cm2 to 2.41 +/- 0.54 cm2. The mean pulmonary artery pressure decreased from 37 +/- 13 mm Hg to 27 +/- 12 mm Hg and the pulmonary vascular resistance decreased from 307 +/- 181 to 238 +/- 122 dynes/s/cm-5. Symptomatic improvement occurred in 272 of the 285 (95%) patients. There were 3 procedure-related deaths (1%). Postdilatation mitral regurgitation was not significant in most patients. Therefore, this procedure can be performed at a low risk with effective results and a fast recovery.

Adult↗
PubMed1990

Angiography, angioscopy, and ultrasound imaging before and after percutaneous balloon angioplasty.

We report two patients undergoing peripheral percutaneous transluminal angioplasty in whom angiography, angioscopy, and ultrasound imaging were performed before and after balloon angioplasty. The first case with smooth atheroma diagnosed by angiography was found to have unrecognized partially occlusive thrombus by angioscopy. After angioplasty, an intimal tear was identified by angioscopy and ultrasound but it was not seen by angiography. The intravascular ultrasound image showed the tear to extend to the adventitia. In the second case, an apparently smooth intimal surface as imaged by angiography was found by angioscopy and ultrasound to have extensive damage, including subintimal hemorrhage, intimal flaps, and arterial dissection at the angioplasty site. These data suggest that the type of information derived from the three imaging techniques is quite different, and that each may have a specific role in intravascular diagnosis.

Aged↗
PubMed1989

Percutaneous (nonsurgical) supported angioplasty in unprotected left main disease and severe left ventricular dysfunction.

A 69-year-old patient with the equivalent of severe, unprotected left main coronary artery disease associated with marked left ventricular dysfunction with ventricular aneurysm who had Class IV angina, underwent supported angioplasty utilizing a total percutaneous approach. The patient tolerated occlusion of his main left coronary artery for a total of 7 minutes without difficulty, during dilatation of left anterior descending and two circumflex lesions. He was discharged the following day, symptom free.

Aged↗
PubMed1988

Percutaneous double balloon aortic valvuloplasty in an adult patient with calcific aortic stenosis and a Bjork-Shiley prosthetic mitral valve.

Percutaneous transluminal balloon valvuloplasty is a new technique in interventional cardiology which to date has been applied successfully in the dilatation of all four cardiac valves. Although the different techniques appear to be quite effective, the safety of these procedures has not been fully explored. In particular, because of the close anatomic relationship of the aortic and mitral annuli, the safety of aortic valvuloplasty in patients with mitral valve prosthesis is unknown. Therefore, we report the applicability of a percutaneous double balloon valvuloplasty in an elderly patient with calcific aortic stenosis and a Bjork-Shiley mitral valve prosthesis.

Aged↗
PubMed1988

Deriving the 12-lead electrocardiogram from four (EASI) electrodes.

Computerized interpretation of the electrocardiogram has now advanced to computerization of the electrocardiograph, resulting in greatly increased versatility, including the capacity for adapting to a variety of lead systems rather than being tethered to the old Einthoven-Wilson-Goldberger (EWG) system. Many varieties of display beyond the 12-lead ECG are also available in software. To date, these new and interesting capabilities have scarcely been exploited. The EASI lead system uses the E, A, and I electrode positions of the Frank lead system, plus an electrode, S, positioned over the upper end of the sternum and, if necessary, ground (anywhere convenient). Its outputs form quasi-xyz signals, x'y'z', that can be approximately transformed into xyz signals by means of a matrix derived from the EASI lead vectors. The result forms a good basis for deriving the 12-lead ECG, using previously published coefficients for the Frank lead system. The match with the conventional ECG can then be improved by statistical means. The results are surprisingly good, and certainly of clinical value. Recent widespread interest in silent ischemia and its detection through Holter monitoring suggests an immediate application which has been rendered practical by the recent introduction of three-channel recorders. The EASI electrode positions give technically satisfactory Holter recordings. Very compact three-channel, multiplexed, radio telemetry equipment is now commercially available and provides another application for the EASI 12-lead ECG.(ABSTRACT TRUNCATED AT 250 WORDS)

Computer Systems↗
PubMed1985

Acid-base determinants of survival after cardiopulmonary resuscitation.

The acid-base and electrolyte conditions which favor survival were examined in 105 patients during and after CPR. There was a sharp decrease in survival when arterial pH exceeded 7.55 during the initial 10 min after initiation of CPR. Measurements made one hour after successful resuscitation also demonstrated an increase in mortality when pH exceeded 7.55. Arterial blood lactate also served as a sensitive quantitative indicator of prognosis, both during and one hour after successful CPR. The adverse effects of alkalemia were largely explained by increases in whole-blood bicarbonate, plasma sodium, and plasma osmolality after administration of sodium bicarbonate.

Acid-Base Equilibrium↗
PubMed1980

Hemostatic changes following rattlesnake (Crotalus viridis helleri) venom in the dog.

Hemostatic changes were observed in mongrel dogs (N = 5, 18.6 26.7 kg) following and i.v. LD20 (50 microgram/kg) of rattlesnake (Crotalus viridis helleri) venom. Venom produced thrombocytopenia within 5 min and fibrinogen was significantly reduced at 240 min. In addition, the presence of fibrin split products, a positive protamine sulfate test and a decrease in the euglobulin lysis time, suggest that fibrinogenolysis and fibrinolysis are initiated shortly after venom. Prothrombin and partial thromboplastin times were little affected. Examination of bone marrow revealed vacuolization and a reduction in the number of megakaryocytes. These data suggest that this dose of rattle-snake venom produces hemostatic defects by the destruction of fibrinogen and circulating platelets.

Animals↗
PubMed1979

Treatment of circulatory shock with dopamine. Studies on survival.

Therapeutic effects of dopamine hydrochloride on the peripheral and metabolic defects of shock were investigated in 34 patients with circulatory shock associated with myocardial infarction, bacteremia, or hypovolemia. Severity of the circulatory defect characterized by hypotension, reduced cardiac output, oliguria, and notably reduced skin (toe) temperature before treatment with dopamine was not directly related to survival. However, the arterial blood concentration of lactate before treatment with dopamine indicated the likelihood of survival. Patients who ultimately survived following treatment with dopamine had normal or only mildly elevated levels of arterial blood lactate before therapy. No patients with established shock states in whom perfusion failure was associated with substantial increases in the level of arterial blood lactate survived regardless of treatment with dopamine. Increases in toe temperature during dopamine treatment also emerged as a uniquely good indicator of favorable outcome during therapy.

Adult↗
PubMedDate not supplied

Transcatheter aortic valve implantation and mitral valve repair: state of the art.

Surgical replacement of cardiac valves evolved significantly since its first use. Evolution of techniques and valves used was driven by the frequent complications encountered with surgically implanted valves. Transcatheter implantation of valves is a new technique which continues to be under investigation and promises to perform a task with less risk and potentially better outcome. In addition, new techniques are being developed to address minimizing mitral regurgitation. Progress in transcatheter valve implantation and catheter mitral annuloplasty is reviewed in this article.

Aortic Valve↗
PubMedDate not supplied

The role of interventional cardiology in pediatric heart transplantation.

Hypoplastic left heart syndrome (HLHS) is the most common cause of cardiac death during the first week of life. The prognosis of this fatal malformation has changed completely since the introduction of neonatal heart transplantation. However, patients awaiting a heart donor are at high risk for closure of the ductus arteriosus and are exposed to complications from indwelling central venous catheters and long-term use of prostaglandin E1. To maintain the ductal patency, which is crucial for the survival of these patients, we performed a stenting of the ductus arteriosus in six infants with HLHS using a 2 cm length balloon expendable stent. Age ranged from 5 to 92 days and weight ranged from 2.1 to 5.4 kg. Successful stenting with subsequent hemodynamic stability was obtained in all the patients. Patient 4 died 24 hours after stenting from hemothorax related to an attempted subclavian catheter placement. Heart transplantation was successfully performed in patients 1, 2, 3, and 5 at 15, 1, 50, and 8 days after stenting, respectively. Patient 6 underwent successful heart transplantation 157 days after ductal stenting.

Biopsy↗