Ronald G. Carere

Angiotensin-Converting Enzyme Inhibition With Quinapril Improves Endothelial Vasomotor Dysfunction in Patients With Coronary Artery Disease

Background Angiotensin-converting enzyme (ACE) inhibitors may exert some of their benefits in the therapy of hypertension, congestive heart failure, and acute myocardial infarction by their improvement of endothelial dysfunction. TREND (Trial on Reversing ENdothelial Dysfunction) investigated whether quinapril might improve endothelial dysfunction in normotensive patients with coronary artery disease and no heart failure, cardiomyopathy, or major lipid abnormalities so that confounding variables that affect endothelial dysfunction could be minimized. Methods and Results Using a double-blind, randomized, placebo-controlled design, we measured the effects of quinapril (40 mg daily) on coronary artery diameter responses to acetylcholine using quantitative coronary angiography. The primary response variable was the net change in the acetylcholine-provoked constriction of target segments between the baseline (prerandomization) and 6-month follow-up angiograms. The constrictive responses to acetylcholine were c...

Percutaneous Transarterial Aortic Valve Replacement in Selected High-Risk Patients With Aortic Stenosis

Background— Percutaneous aortic valve replacement represents an endovascular alternative to conventional open heart surgery without the need for sternotomy, aortotomy, or cardiopulmonary bypass. Methods and Results— Transcatheter implantation of a balloon-expandable stent valve using a femoral arterial approach was attempted in 50 symptomatic patients with severe aortic stenosis in whom there was a consensus that the risks of conventional open heart surgery were very high. Valve implantation was successful in 86% of patients. Intraprocedural mortality was 2%. Discharge home occurred at a median of 5 days (interquartile range, 4 to 13). Mortality at 30 days was 12% in patients in whom the logistic European System for Cardiac Operative Risk Evaluation risk score was 28%. With experience, procedural success increased from 76% in the first 25 patients to 96% in the second 25 (P=0.10), and 30-day mortality fell from 16% to 8% (P=0.67). Successful valve replacement was associated with an increase in echocardiographic valve area from 0.6±0.2 to 1.7±0.4 cm2. Mild paravalvular regurgitation was common but was well tolerated. After valve insertion, there was a significant improvement in left ventricular ejection fraction (P<0.0001), mitral regurgitation (P=0.01), and functional class (P<0.0001). Improvement was maintained at 1 year. Structural valve deterioration was not observed with a median follow-up of 359 days. Conclusion— Percutaneous valve replacement may be an alternative to conventional open heart surgery in selected high-risk patients with severe symptomatic aortic stenosis.

Percutaneous Aortic Valve Implantation Retrograde From the Femoral Artery

Background— Percutaneous aortic valve implantation by an antegrade transvenous approach has been described but is problematic. Retrograde prosthetic aortic valve implantation via the femoral artery has potential advantages. Percutaneous prosthetic aortic valve implantation via the femoral arterial approach is described and the initial experience reported. Methods and Results— The valve prosthesis is constructed from a stainless steel stent with an attached trileaflet equine pericardial valve and a fabric cuff. After routine aortic balloon valvuloplasty, a 22F or 24F sheath is advanced from the femoral artery to the aorta. A steerable, deflectable catheter facilitates manipulation of the prosthesis around the aortic arch and through the stenotic valve. Rapid ventricular pacing is used to reduce cardiac output while the delivery balloon is inflated to deploy the prosthesis within the annulus. Percutaneous aortic prosthetic valve implantation was attempted in 18 patients (aged 81±6 years) in whom surgical risk was deemed excessive because of comorbidities. Iliac arterial injury, seen in the first 2 patients, did not recur after improvement in screening and access site management. Implantation was successful in 14 patients. After successful implantation, the aortic valve area increased from 0.6±0.2 to 1.6±0.4 cm2. There were no intraprocedural deaths. At follow-up of 75±55 days, 16 patients (89%) remained alive. Conclusions— This initial experience suggests that percutaneous transarterial aortic valve implantation is feasible in selected high-risk patients with satisfactory short-term outcomes.

Angiotensin-Converting Enzyme Inhibition With Quinapril Improves Endothelial Vasomotor Dysfunction in Patients With Coronary Artery Disease The TREND (Trial on Reversing ENdothelial Dysfunction) Study

BACKGROUND Angiotensin-converting enzyme (ACE) inhibitors may exert some of their benefits in the therapy of hypertension, congestive heart failure, and acute myocardial infarction by their improvement of endothelial dysfunction. TREND (Trial on Reversing ENdothelial Dysfunction) investigated whether quinapril might improve endothelial dysfunction in normotensive patients with coronary artery disease and no heart failure, cardiomyopathy, or major lipid abnormalities so that confounding variables that affect endothelial dysfunction could be minimized. METHODS AND RESULTS Using a double-blind, randomized, placebo-controlled design, we measured the effects of quinapril (40 mg daily) on coronary artery diameter responses to acetylcholine using quantitative coronary angiography. The primary response variable was the net change in the acetylcholine-provoked constriction of target segments between the baseline (prerandomization) and 6-month follow-up angiograms. The constrictive responses to acetylcholine were comparable in the placebo (n = 54) and quinapril (n = 51) groups at baseline. After 6 months, only the quinapril group showed significant net improvement in response to incremental concentrations of acetylcholine (4.5 +/- 3.0% [mean +/- SEM] versus -0.1 +/- 2.8% at 10(-6) mol/L and 12.1 +/- 3.0% versus -0.8 +/- 2.9% at 10(-4) mol/L, quinapril versus placebo, respectively; overall P = .002). CONCLUSIONS TREND shows that ACE inhibition with quinapril improved endothelial dysfunction in patients who were normotensive and who did not have severe hyperlipidemia or evidence of heart failure. These benefits of ACE inhibition are likely due to attenuation of the contractile effects and superoxide-generating effects of angiotensin II and to enhancement of endothelial cell release of nitric oxide secondary to diminished breakdown of bradykinin.

Transapical Transcatheter Aortic Valve Implantation in Humans Initial Clinical Experience

Background— Aortic valve replacement with cardiopulmonary bypass is currently the treatment of choice for symptomatic aortic stenosis but carries a significant risk of morbidity and mortality, particularly in patients with comorbidities. Recently, percutaneous transfemoral aortic valve implantation has been proposed as a viable alternative in selected patients. We describe our experience with a new, minimally invasive, catheter-based approach to aortic valve implantation via left ventricular apical puncture without cardiopulmonary bypass or sternotomy. Methods and Results— A left anterolateral intercostal incision is used to expose the left ventricular apex. Direct needle puncture of the apex allows introduction of a hemostatic sheath into the left ventricle. The valve prosthesis, constructed from a stainless steel stent with an attached trileaflet equine pericardial valve, is crimped onto a valvuloplasty balloon. The prosthetic valve and balloon catheter are passed over a wire into the left ventricle. Positioning within the aortic annulus is confirmed by fluoroscopy, aortography, and echocardiography. Rapid ventricular pacing is used to reduce cardiac output while the balloon is inflated, deploying the prosthesis within the annulus. Transapical aortic valve implantation was successfully performed in 7 patients in whom surgical risk was deemed excessive because of comorbidities. Echocardiographic median aortic valve area increased from 0.7±0.1 cm2 (interquartile range) to 1.8±0.8 cm2 (interquartile range). There were no intraprocedural deaths. At a follow up of 87±56 days, 6 of 7 patients remain alive and well. Conclusions— This initial experience suggests that transapical aortic valve implantation without cardiopulmonary bypass is feasible in selected patients with aortic stenosis.

Co-morbidity data in outcomes research Are clinical data derived from administrative databases a reliable alternative to chart review?

Evaluation of co-morbidity data is essential in health outcomes research. Co-morbidity data derived from administrative databases has been criticized for lacking the accuracy required for clinical research. We compared co-morbidity data derived from a Canadian provincial hospitalization database with chart review in 817 adults treated with a percutaneous coronary intervention at a single tertiary care hospital between 1994 and 1995. While the administrative database tended to under-estimate the prevalence of some co-morbid conditions, the agreement between chart review and administrative data was good to very good for most conditions. Asymptomatic conditions were noted to have lower levels of agreement. Multivariate risk models for all-cause mortality constructed from both data sources were almost identical, suggesting minimal misclassification. The results indicate that clinical data abstracted from most Canadian hospitalization databases can provide reliable information regarding baseline co-morbid conditions believed to influence survival in a population undergoing percutaneous coronary interventions.

Percutaneous coronary intervention for cardiogenic shock in the SHOCK trial

OBJECTIVES We examined the clinical, angiographic, and procedural characteristics determining survival after percutaneous coronary intervention (PCI) for cardiogenic shock. BACKGROUND The SHOCK (SHould we emergently revascularize Occluded coronaries for Cardiogenic shocK?) trial prospectively enrolled patients with shock complicating acute myocardial infarction (MI). Patients were randomized to a strategy of early revascularization or initial medical stabilization. METHODS Patients randomized to early revascularization underwent PCI or bypass surgery on the basis of predefined clinical criteria. Patients randomized to early revascularization who underwent PCI and had angiographic films available for analysis are the subject of this report (n = 82). RESULTS The median time from MI to PCI was 11 h. The majority of patients had occluded culprit arteries (Thrombolysis In Myocardial Infarction [TIMI] grade 0 or 1 flow in 62%) and multivessel disease (81%). One-year mortality in PCI patients was 50%. Mortality was 39% if PCI was successful but 85% if unsuccessful (p < 0.001). Mortality was 38% if TIMI flow grade 3 was achieved, 55% with TIMI grade 2 flow, and 100% with TIMI grade 0 or 1 flow (p < 0.001). Mortality was 67% if severe mitral regurgitation was documented. Independent correlates of mortality were as follows: increasing age (p < 0.001), lower systolic blood pressure (p = 0.009), increasing time from randomization to PCI (p = 0.019), lower post-PCI TIMI flow (0/1 vs. 2/3) (p < 0.001), and multivessel PCI (p = 0.040). CONCLUSIONS Restoration of coronary blood flow is a major predictor of survival in cardiogenic shock. Benefit appears to extend beyond the generally accepted 12-h post-infarction window. Surgery should be considered in shock patients with severe mitral insufficiency or multivessel disease not amenable to relatively complete percutaneous revascularization.

Transapical transcatheter aortic valve implantation: follow-up to 3 years.

BACKGROUND We performed the first human case of successful transapical transcatheter aortic valve implantation on a beating heart in October 2005, and therefore we have the longest follow-up on transapical aortic valve implantation in humans. We now report clinical and echocardiographic outcomes of transapical aortic valve implantation in 71 patients. METHODS Between October 2005 and February 2009, 71 patients (44 female) underwent transcatheter transapical aortic valve implantation with either 23- or 26-mm Edwards Lifesciences transcatheter bioprostheses. All patients with symptomatic aortic stenosis were declined for conventional aortic valve replacement owing to unacceptable operative risks and were not candidates for transfemoral aortic valve implantation because of poor arterial access. Clinical and echocardiographic follow-ups were performed before discharge, at 1 and 6 months, and then yearly. The mean follow-up was 12.9 +/- 11.5 months with a total of 917.3 months of follow-up. RESULTS Mean age was 80.0 +/- 8.1 years and predicted operative mortality was 34.5% +/- 20.4% by logistic EuroSCORE and 12.1% +/- 7.7% by The Society of Thoracic Surgeons Risk Calculator. Valves were successfully implanted in all patients. Twelve patients died within 30 days (30-day mortality: 16.9% in all patients, 33% in the first 15 patients, and 12.5% in the remainder), and 10 patients died subsequently. Overall survival at 24 and 36 months was 66.3% +/- 6.4% and 58.0% +/- 9.5%, respectively. Among 59 patients who survived at least 30 days, 24- and 36-month survivals were 79.8% +/- 6.4% and 69.8% +/- 10.9%, respectively. Late valve-related complications were rare. New York Heart Association functional class improved significantly from preoperative 3.3 +/- 0.8 to 1.8 +/- 0.8 at 24 months. The aortic valve area and mean gradient remained stable at 24 months (1.6 +/- 0.3 cm(2) and 10.3 +/- 5.9 mm Hg, respectively). CONCLUSION Our outcome suggests that transapical transcatheter aortic valve implantation provides sustained clinical and hemodynamic benefits for up to 36 months in selected high-risk patients with symptomatic severe aortic stenosis.

Transapical transcatheter aortic valve implantation: 1-year outcome in 26 patients

BACKGROUND We reported the first case of successful transapical transcatheter aortic valve implantation in a human subject in 2005 and have now completed a 12-month follow-up on our first 26 patients. This is, to date, the longest follow-up of patients undergoing transapical aortic valve implantation. METHODS Between October 2005 and January 2007, 26 patients (13 female) underwent transcatheter transapical aortic valve implantation with either 23- or 26-mm Edwards Lifesciences transcatheter bioprostheses. All patients with symptomatic aortic stenosis were declined for conventional aortic valve replacement because of unacceptable operative risks and were not candidates for transfemoral aortic valve implantation because of poor arterial access. Clinical and echocardiographic follow-up was performed before discharge and at 1, 6, and 12 months. Data from the 17 patients who survived over 12 months were used for comparisons of the baseline and follow-up results. RESULTS The mean age was 80 +/- 9 years, and the predicted operative mortality was 37% +/- 20% by using logistic EuroSCORE and 11% +/- 6% by using the Society of Thoracic Surgeons Risk Calculator. Valves were successfully implanted in all patients. Six patients died within 30 days (30-day mortality, 23%), and 3 patients died from noncardiovascular causes after 30 days (late mortality, 12%). Among patients who survived at least 30 days, 12-month survival was 85%. There were no late valve-related complications. New York Heart Association functional class improved significantly. The aortic valve area and mean gradient remained stable at 12 months (1.6 +/- 0.3 cm(2) and 9.6 +/- 4.8 mm Hg, respectively). CONCLUSION Our 1-year clinical and echocardiographic outcomes suggest that transapical transcatheter aortic valve implantation is a viable alternative to conventional aortic valve replacement in selected high-risk patients.

Prevention and management of transcatheter balloon-expandable aortic valve malposition†

Early clinical outcomes in selected high‐risk patients undergoing catheter‐based aortic valve replacement (AVR) compare favorably with conventional surgical AVR. Improved understanding of the mechanisms of success and failure of transcatheter AVR will likely improve outcomes further. To this end, we examined our experience during the developmental phases of transcatheter AVR and describe the causes and management of prosthetic valve malposition.