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C E Ruiz

Publications and source records attributed to C E Ruiz.

At least 37 records · Page 2Linked to original sources
PubMed1995

A novel method for treatment of abdominal aortic aneurysms using percutaneous implantation of a newly designed endovascular device.

BACKGROUND: Percutaneous implantation of a stent to bridge abdominal aortic aneurysm (AAA) may provide an alternative to surgical reconstruction in patients with this serious disorder. We developed a self-expandable, stainless steel, woven mesh endovascular device with a delivery catheter and studied its efficacy in a canine model of AAA. METHODS AND RESULTS: Infrarenal AAAs were created surgically in eight adult dogs using autologous tissue. Two types of endovascular stents were used in this study; a plain or uncovered stent, about 14 mm in diameter in the unconstrained configuration, and a covered stent, coated by porous polyurethane, about 16 mm in diameter. All stents were successfully placed on the first attempt. Aortograms revealed a mean aneurysm diameter of 1.86 +/- 0.47 cm, an average of 70% larger than the reference aortic lumen before stent placement. After stent placement, aortograms showed that the aneurysmal cavity disappeared completely in three dogs treated with a covered stent and that the aortic blood flow into the cavity markedly reduced, with faint contrast filling the cavity in the remaining five dogs treated with an uncovered stent. The uncovered stent was intentionally placed across the major arterial branches in two dogs. No acute complications were encountered at the time of stent placement. Two dogs were killed shortly after the procedure for immediate evaluation of the device, which was found to be in place and patent. One dog in which a covered stent was placed was euthanized 2 1/2 weeks later because of paraplegia secondary to a spinal cord infarction noted 48 hours after stent placement. Postmortem study revealed thrombus occluding the stent lumen. The remaining five dogs tolerated the devices well and completed 4 weeks of follow-up. Premortem aortograms showed no residual aneurysmal cavity in four dogs and only a small cavity in one dog that had received an uncovered stent. All stents were fully patent with no thrombus and were either completely or partially surfaced by neointima. Importantly, the major arterial branches over which the uncovered stents were placed were widely patent without obstruction by neointima. CONCLUSIONS: This study demonstrates the feasibility of percutaneous implantation of this new device and its effectiveness in the treatment of surgically created AAA in our canine model. The covered stent was able to exclude AAA immediately upon deployment and is of potential value in the emergency treatment of leaking AAAs. The uncovered stent appears to safely bridge branch arteries as well as significantly reduce the angiographic size of the aneurysm and may be useful in the elective therapy of AAAs. These results are promising, and future clinical trials to investigate the safety and efficacy of this device in humans are warranted.

Animals↗
PubMed1995

Immediate and late outcome of percutaneous balloon mitral valvotomy in patients with significantly calcified valves.

We assessed immediate and late outcome in 55 patients with significantly calcified valves (group 1) after balloon mitral valvotomy and compared the results with those from 60 patients with noncalcified or minimally calcified valves (group 2). After valvotomy, mitral valve area increased from 1.03 +/- 0.30 cm2 to 1.64 +/- 0.35 cm2 (p = 0.0001) by echo planimetry in group 1 but was significantly smaller than the mitral valve area in group 2 after valvotomy (1.94 +/- 0.38 cm2; p = 0.0001). At a mean follow-up period of 30 months (range 2 to 81 months), 51% of patients in group 1 and 83% in group 2 were symptom free (p = 0.0002). In group 2, 15 (27%) patients and in group 2, 4 (7%) patients had cardiac events (p = 0.003). The risk ratio for cardiac events was 4.3 times greater in group 1 than in group 2. In group 1, the risk ratio for cardiac events was 3.2 times higher in patients age > or = 65 years and in patients with atrial fibrillation. The 6-year cumulative cardiac event-free survival rate was 64% in group 1 and 90% in group 2 (p = 0.005). In 75 (65%) patients who had follow-up echocardiographic study (35 in group 1 and 40 in group 2), mitral valve area decreased to 1.48 +/- 0.42 cm2 at follow-up in group 1 (p < 0.01) and to 1.77 +/- 0.50 cm2 in group 2 (p = 0.3). Restenosis occurred in 16 (46%) of 35 patients in group 1 and 10 (25%) of 40 in group 2 (p = 0.06).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Comparison of late outcome between Inoue balloon and double-balloon techniques for percutaneous mitral valvotomy in a matched study.

The follow-up results between Inoue balloon (n = 43, group 1) and double-balloon (n = 43, group 2) mitral valvotomies were compared in a patient-to-patient matched study. Matching was based on patients' age, mitral valve echo score, fluoroscopic calcification, mitral valve area before valvotomy, and follow-up period. The mean follow-up period was 13 +/- 9 months for both groups. At follow-up, 72% of patients were symptom free in each group; 2 (4.7%) patients in group 1 and 1 (2.3%) patient in group 2 underwent mitral valve replacement surgery. Of these 3 patients, 2 died after surgery, 1 from each group. The mitral valve area by Doppler was 1.8 +/- 0.3 cm2 in group 1 and 1.8 +/- 0.4 cm2 in group 2 (p = 0.7); the area by echo planimetry was 1.7 +/- 0.3 cm2 in group 1 and 1.8 +/- 0.3 cm2 in group 2 (p = 0.3) at follow-up. Restenosis occurred in 5 (12%) patients from each group. The cumulative restenosis-free rate was 96% at 1 years, 78% at 2 years, and 58% at 3 years in group 1 and 98%, 76%, and 51%, respectively, in group 2 (p = 0.8). Balloon selection did not appear to influence the clinical outcome at follow-up. We conclude that both the inoue balloon and the double-balloon valvotomies are effective therapies with comparable follow-up results for patients with mitral stenosis.

Adult↗
PubMed1994

Thermodilution left-sided cardiac output for valve area determination after balloon mitral valvotomy.

This study was conducted to establish the validity of left-sided cardiac output measurement with a Swan-Ganz catheter and assess its accuracy in estimating mitral valve area (MVA) by the Gorlin formula. The use of right-sided cardiac output after balloon mitral valvotomy (BMV) can give inaccurate measurements for Gorlin-derived MVA because of the atrial septal defect (ASD) created during the procedure. The left-sided cardiac output was measured with a Swan-Ganz catheter (proximal port in the left atrium and then in the left ventricle, and distal port in the ascending aorta) in 10 consecutive patients before and after BMV. Gorlin-derived MVA cardiac output by this method was compared with (1) Gorlin-derived MVA by means of right-sided cardiac output with and without balloon occlusion of the ASD and (2) MVA measured by echocardiography. Before BMV, a close agreement with a good correlation between left-sided and right-sided cardiac output was found (r = 0.83, p = 0.006). Furthermore, Gorlin-derived MVA by cardiac output with either method was comparable with valve area by echo. After BMV, left-sided cardiac output correlated well (r = 0.92, p = 0.0002) and was comparable with right-sided cardiac output with occlusion of the ASD (mean difference 0.17 +/- 0.49 L/min, p = 0.3) but was significantly lower than the value obtained with open ASD (mean difference 0.93 +/- 0.77 L/min, p = 0.004). Comparison of the correspondent MVAs yielded similar results. Gorlin-derived MVA with left-sided cardiac output and MVA by echo were also similar.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Output↗
PubMed1994

Late clinical and echocardiographic follow up after percutaneous balloon dilatation of the mitral valve.

OBJECTIVE: To assess the outcome after attempted percutaneous balloon dilatation of the mitral valve in patients with severe mitral stenosis between February 1986 and June 1992. DESIGN: Clinical state, mitral valve area, and restenosis at follow up were analysed. Mitral valve area as determined by the Gorlin formula, planimetry, and Doppler methods was compared before and after dilatation and at follow up. SETTING: University hospital. PATIENTS: 176 patients had serial clinical and Doppler echocardiographic follow up and 44 of them also underwent recatheterisation. RESULT: At follow up 93% of patients were in New York Heart Association functional class I or class II. Mitral valve area (planimetry) increased from 0.97(0.24) cm2 before to 1.86(0.39) cm2 after dilatation (p = 0.0001) and then decreased to 1.72(0.39) cm2 at follow up (p < 0.001); mitral valve area (Doppler) increased from 1.01 (0.24) to 1.89 (0.42) cm2 (p = 0.0001) and then decreased to 1.78(0.40) cm2 (p < 0.05). The overall restenosis rate was 15% and over 90% of the patients were free from cardiovascular events. Age, valvar calcification, echocardiographic score, and mitral valve area after dilatation were found to be determinant predictors of restenosis. In patients who underwent recatheterisation, mitral valve area by the Gorlin method at follow up was comparable with that by planimetry and Doppler methods whereas a significant discrepancy between the three methods was noted immediately after dilatation. CONCLUSION: Balloon dilatation of the mitral valve provided sustained anatomical and functional improvement in over 80% of patients at late follow up. Older age, heavy calcification, high echocardiographic score, and suboptimal immediate results are significant predictors of restenosis. Doppler echocardiographic examination is the procedure of choice for follow up evaluation.

Adolescent↗
PubMed1993

Sequential directional atherectomy of coronary bifurcation lesions.

Conventional techniques of coronary angioplasty for lesions at coronary bifurcations are well documented, are sometimes cumbersome, and have inherent limitations. We describe a technique for sequential atherectomy at coronary bifurcations. Further evaluation is needed to determine the overall safety, efficacy, applicability and durability of sequential directional atherectomy at coronary bifurcations.

Adult↗
PubMed1992

Percutaneous closure of a secundum atrial septal defect and double balloon valvotomies of a severe mitral and aortic valve stenosis in a patient with Lutembacher's syndrome and severe pulmonary hypertension.

This is a 43-yr-old female presenting with recurrent atrial septal defect, closed surgically, 10 years prior, severe aortic and mitral stenosis, and severe tricuspid regurgitation. She was considered inoperable because of the severe pulmonary hypertension and the complexity of the disease. A percutaneous umbrella closure of the atrial septal defect in conjunction with mitral and aortic balloon valvotomies could be safely and successfully performed. After significant clinical and hemodynamic improvement, surgery was judged feasible, but was refused by the patient who suddenly expired 8 weeks later. The usefulness of percutaneous therapy as a rescue procedure and the management of patients with Eisenmenger's physiology are discussed.

Adult↗
PubMed1992

Comparison of Inoue single-balloon versus double-balloon technique for percutaneous mitral valvotomy.

The results of percutaneous mitral valvotomy by means of the Inoue single-balloon (N = 85, group 1) and the double-balloon (N = 322, group 2) techniques were compared in a nonrandomized study. The groups were not significantly different with regard to age, sex, calcification, or hemodynamic values before percutaneous mitral valvotomy. After percutaneous mitral valvotomy, patients in both groups had significant hemodynamic and clinical improvement. The increases in mitral valve area and cardiac output and the decreases in mitral valve gradient, mean pulmonary artery pressure, and mean left atrial pressure were greater in group 2. Mitral valve area determined by the Gorlin method increased 191% in group 2 and 106% in group 1; Doppler-determined mitral valve area increased 133% in group 2 and 98% in group 1. Optimal results were achieved in 93% of the patients in group 2 and 76% in group 1 (p less than or equal to 0.0001). In group 1, 6% of patients had a left-to-right shunt as shown by angiography versus 14% in group 2 (p less than or equal to 0.05). In group 2, 46% of patients had at least a 1+ increase in mitral regurgitation versus 52% in group 1. Among the patients who had an increase in mitral regurgitation, 36% of those in group 1 versus 9% in group 2 had a 2+ or more increase (p less than or equal to 0.001). The mean balloon diameter to anulus ratio was larger in group 2, and the larger the balloon diameter to anulus ratio, the greater the increase in mitral valve area.(ABSTRACT TRUNCATED AT 250 WORDS)

Catheterization↗