Wes R. Pedersen

A Regional System to Provide Timely Access to Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction

Background— Percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) is superior to fibrinolysis when performed in a timely manner in high-volume centers. Recent European trials suggest that transfer for PCI also may be superior to fibrinolysis and increase access to PCI. In the United States, transfer times are consistently long; therefore, many believe a transfer for PCI strategy for STEMI is not practical. Methods and Results— We developed a standardized PCI-based treatment system for STEMI patients from 30 hospitals up to 210 miles from a PCI center. From March 2003 to November 2006, 1345 consecutive STEMI patients were treated, including 1048 patients transferred from non-PCI hospitals. The median first door-to-balloon time for patients <60 miles (zone 1) and 60 to 210 miles (zone 2) from the PCI center was 95 minutes (25th and 75th percentiles, 82 and 116 minutes) and 120 minutes (25th and 75th percentiles, 100 and 145 minutes), respectively. Despite the high-risk unselected patient population (cardiogenic shock, 12.3%; cardiac arrest, 10.8%; and elderly [≥80 years of age], 14.6%), in-hospital mortality was 4.2%, and median length of stay was 3 days. Conclusions— Rapid transfer of STEMI patients from community hospitals up to 210 miles from a PCI center is safe and feasible using a standardized protocol with an integrated transfer system.

Acute and 12-Month Results With Catheter-Based Mitral Valve Leaflet Repair : The EVEREST II (Endovascular Valve Edge-to-Edge Repair) High Risk Study

OBJECTIVES The EVEREST II (Endovascular Valve Edge-to-Edge Repair) High Risk Study (HRS) assessed the safety and effectiveness of the MitraClip device (Abbott Vascular, Santa Clara, California) in patients with significant mitral regurgitation (MR) at high risk of surgical mortality rate. BACKGROUND Patients with severe MR (3 to 4+) at high risk of surgery may benefit from percutaneous mitral leaflet repair, a potentially safer approach to reduce MR. METHODS Patients with severe symptomatic MR and an estimated surgical mortality rate of ≥12% were enrolled. A comparator group of patients screened concurrently but not enrolled were identified retrospectively and consented to compare survival in patients treated by standard care. RESULTS Seventy-eight patients underwent the MitraClip procedure. Their mean age was 77 years, >50% had previous cardiac surgery, and 46 had functional MR and 32 degenerative MR. MitraClip devices were successfully placed in 96% of patients. Protocol-predicted surgical mortality rate in the HRS and concurrent comparator group was 18.2% and 17.4%, respectively, and Society of Thoracic Surgeons calculator estimated mortality rate was 14.2% and 14.9%, respectively. The 30-day procedure-related mortality rate was 7.7% in the HRS and 8.3% in the comparator group (p = NS). The 12-month survival rate was 76% in the HRS and 55% in the concurrent comparator group (p = 0.047). In surviving patients with matched baseline and 12-month data, 78% had an MR grade of ≤2+. Left ventricular end-diastolic volume improved from 172 ml to 140 ml and end-systolic volume improved from 82 ml to 73 ml (both p = 0.001). New York Heart Association functional class improved from III/IV at baseline in 89% to class I/II in 74% (p < 0.0001). Quality of life was improved (Short Form-36 physical component score increased from 32.1 to 36.1 [p = 0.014] and the mental component score from 45.5 to 48.7 [p = 0.065]) at 12 months. The annual rate of hospitalization for congestive heart failure in surviving patients with matched data decreased from 0.59 to 0.32 (p = 0.034). CONCLUSIONS The MitraClip device reduced MR in a majority of patients deemed at high risk of surgery, resulting in improvement in clinical symptoms and significant left ventricular reverse remodeling over 12 months. (Pivotal Study of a Percutaneous Mitral Valve Repair System [EVEREST II]; NCT00209274).

Intravenous diltiazem for the treatment of patients with atrial fibrillation or flutter and moderate to severe congestive heart failure

The objective of this multicenter, randomized, double-blind, placebo-controlled study was to determine the safety and efficacy of intravenous diltiazem in the treatment of 37 patients with rapid (ventricular rate, mean +/- SD 142 +/- 17 beats/min) atrial fibrillation or flutter and moderate to severe congestive heart failure (ejection fraction, mean +/- SD 36 +/- 14%; New York Heart Association class III [23 patients], class IV [14 patients]). During the double-blind portion of the study, patients received either intravenous diltiazem, 0.25 mg/kg over 2 minutes, or placebo followed 15 minutes later by diltiazem or placebo, 0.35 mg/kg over 2 minutes, if the first dose was tolerated but ineffective. Placebo nonresponders were given open-label intravenous diltiazem in a similar fashion as in the double-blind portion of the study. In the double-blind part of the study, 21 (18 with 0.25 mg/kg, 3 with an additional 0.35 mg/kg) of the 22 patients (95%) responded to diltiazem, and 0 of 15 patients (0%) responded to placebo (p < 0.001). All 15 patients (13 with 0.25 mg/kg and 2 with an additional 0.35 mg/kg) who received placebo during the double-blind period had a therapeutic response to diltiazem during open-label therapy. Overall, 36 of 37 patients (97%) had a therapeutic response to intravenous diltiazem. Heart rate response to diltiazem after the 2-minute bolus infusions consisted of a > or = 20% decrease in heart rate from baseline in 36 patients; in addition, 17 patients also had heart rates decreased to < 100 beats/min, whereas no patient had conversion to sinus rhythm.(ABSTRACT TRUNCATED AT 250 WORDS)

iCoapsys mitral valve repair system: Percutaneous implantation in an animal model.

Objective: Determine if the iCoapsys device could be accurately and safely implanted using a novel transcatheter system. Background: Functional mitral regurgitation is a ventricular disease characterized by mitral insufficiency in the absence of structural valve abnormalities. It occurs in the presence of ischemic or non‐ischemic cardiomyopathy. The Coapsys (surgical) transventricular device, currently undergoing randomized evaluation, offers a more integrated treatment strategy. Methods: The iCoapsys transcatheter mitral valve repair system was developed for percutaneous delivery of an implant designed to emulate the surgical (i.e. Coapsys) device. Nine operators tested the ability of this novel catheter system to successfully deliver and position the iCoapsys implant in 12 adult sheep. Results: Post mortem evaluation in this acute model demonstrated precise percutaneous delivery and implantation in all 12 animals using fluoroscopic, coronary angiographic, and epicardial echo guidance. There was no excessive bleeding, hemodynamic compromise or sustained arrhythmias. Conclusions: A novel transcatheter methodology was developed to consistently deliver and accurately position the iCoapsys implant. The percutaneous iCoapsys system was successfully implanted without complication in this acute animal model series.

Exclusion of Atrial Thrombus by Transesophageal Echocardiography

To determine whether transesophageal echocardiography (TEE) is useful in ruling out the presence of atrial thrombus, we performed TEE in 20 patients immediately before valve replacement or valve repair and within 3 days of an autopsy in one patient. Mitral stenosis was the predominant lesion in three patients, mitral regurgitation was seen in 11 patients, five patients had mitral prosthesis malfunction, one patient had a tricuspid prosthesis malfunction, and one patient had aortic stenosis. Eight patients were in atrial fibrillation. Four patients demonstrated spontaneous contrast in the associated atria. Nine patients were receiving oral anticoagulation. Mean left atrial diameter was 5.3 +/- 1.3 mm. TEE revealed no evidence for atrial thrombus in 18 of the 21 patients; this finding was confirmed by careful inspection of the atria including the appendages. TEE demonstrated a left atrial thrombus in two patients and a right atrial thrombus in another (confirmed at the time of surgery or at autopsy). In all cases transthoracic echocardiography was negative. Our data suggest that TEE is useful in ruling out atrial thrombus, and therefore may be a useful test preceding interventions associated with an increased risk of embolism from the atria such as cardioversion, mitral valvuloplasty, or valve replacement.

Radiation following percutaneous balloon aortic valvuloplasty to prevent restenosis (RADAR pilot trial)

Objectives: We wished to determine the feasibility and early safety of external beam radiation therapy (EBRT) used following balloon aortic valvuloplasty (BAV) to prevent restenosis. Background: BAV for calcific aortic stenosis (AS) has been largely abandoned because of high restenosis rates, i.e., > 80% at 1 year. Radiation therapy is useful in preventing restenosis following vascular interventions and treating other benign noncardiovascular disorders. Methods: We conducted a 20‐patient, pilot study evaluating EBRT to prevent restenosis following BAV in elderly patients with calcific AS. Total doses ranging from 12–18 Gy were delivered in fractions over a 3–5 day post‐op period to the aortic valve. Echocardiography was performed pre and 2 days post‐op, 1, 6, and 12 months following BAV. Results: One‐year follow‐up is completed (age 89 ± 4). There were no complications related to EBRT. Eight patients died prior to 1 year; 5 of 10 (50%) in the low‐dose (12 Gy) group and 3 of 10 (30%) in the high‐dose (15–18 Gy) group. None of these 8 patients had restenosis, i.e., > 50% loss of the initial AVA gain, and only three deaths were cardiac in origin. One patient underwent aortic valve replacement and none repeated BAV. By 1 year, 3 of the initial 10 (30%) in the low‐dose group and 1 of 9 (11%) in the high‐dose group demonstrated restenosis (21% overall). Conclusions: EBRT following BAV in elderly patients with AS is feasible, free of early complications, and holds promise in reducing the 1 year restenosis rate in a dose‐dependent fashion.

Transesophageal echocardiography in patients with mechanical circulatory assistance

Transesophageal echocardiography was used to assess myocardial function and to detect complications after mechanical circulatory support for 8 patients with cardiogenic shock. In 3 of 8 patients, serial transesophageal echocardiography documented improvement of systolic ventricular function, and it was possible to wean these 3 patients from the ventricular assist device. In all patients, transesophageal echocardiography added clinically important information including the extent of left and right ventricular dysfunction (6 patients), presence of atrial or ventricular thrombus (5 patients), presence of pericardial effusion or clot (2 patients), and verification of the position of the intravascular device (1 patient). Thus, transesophageal echocardiography may provide clinically useful information regarding both the underlying cardiac disease and potential complications from the mechanical circulatory assistance.

Feasibility of transcatheter intervention for severe aortic stenosis in patients ≥90 years of age: Aortic valvuloplasty revisited

The goals of this study were to determine the feasibility, safety, and early outcomes of balloon aortic valvuloplasty (BAV) for severe aortic stenosis in a nonagenarian population.

Comparison of Outcomes in High-Risk Patients >70 Years of Age With Aortic Valvuloplasty and Percutaneous Coronary Intervention Versus Aortic Valvuloplasty Alone

The goal of this study was to compare outcomes of combined balloon aortic valvuloplasty (BAV) plus percutaneous coronary intervention (PCI) with BAV alone in a surgically high risk, older (>70 years) population with both aortic stenosis (AS) and coronary artery disease (CAD). The medical records, coronary angiograms, and procedural reports of 100 consecutive patients who underwent BAV and coronary angiography at our institution from July 2003 to November 2006 were reviewed. Seventeen patients (mean age 86.2+/-6.4 years) underwent combined (nonstaged) BAV and PCI with a calculated Society of Thoracic Surgery risk score of 13.5%+/-6.7; 13 of these underwent coronary stenting before BAV and 4 after BAV. All 17 patients were successfully treated with this combined strategy. The incidence of periprocedural mortality, myocardial infarction, and stroke was zero. An additional 25 patients (mean age 85.9+/-6.9) with CAD were identified who underwent BAV alone with a Society of Thoracic Surgery risk score of 12.6+/-5.7%. PCI in these patients was avoided primarily because of greater lesion complexity or a perceived low probability of symptomatic benefit. There was 1 procedural death, no myocardial infarction, and 1 postprocedural stroke in these 25 patients. The procedural duration and hospital length of stay for the combined BAV and PCI group was 98.8+/-17.6 minutes and 4.1+/-2.8 days, respectively, and for the BAV only group was 86.2+/-27.3 minutes and 3.3+/-2.1 days, respectively. In conclusion, with appropriate selection, BAV plus PCI was safely performed in this retrospective series of elderly, high-risk patients with severe AS and CAD.

Transesophageal color Doppler echocardiography of the normal St. Jude medical mitral valve prosthesis

Transesophageal color flow Doppler findings are reported in 36 patients with a St. Jude Medical mechanical mitral valve prosthesis who had no auscultatory evidence for prosthetic valve dysfunction. Multiple jets consistent with mitral regurgitation originating from the central and lateral portion of the prosthesis were found in all patients. Maximum jet length ranged from 11 to 51 mm (mean 21 +/- 9 mm). Maximum jet area ranged from 0.2 to 4.1 cm3 (mean 1.2 +/- 0.9 cm2). The color M-mode Doppler interrogation showed two distinct components of the regurgitant jet: brief early systolic flow consistent with valve closure followed by holosystolic regurgitant flow consistent with transvalvular leakage. Four patients (11%) had a maximum regurgitant jet length exceeding 30 mm and absence of early systolic closure regurgitant flow by M-mode color imaging, suggesting clinically silent paravalvular leakage. Two pin-sized paravalvular suture line defects were confirmed in one patient at cardiac transplantation. We conclude that transesophageal echocardiography is a highly sensitive method for detection of mitral regurgitation in the St. Jude Medical mitral prosthesis. Clinically silent paravalvular leakage should be suspected if the maximum jet length exceeds 30 mm and color M-mode interrogation fails to demonstrate an early systolic closure regurgitant flow component.