Pathophysiology of exercise heart rate recovery: a comprehensive analysis.

Expanded use of exercise heart rate recovery (HRR) has renewed interest in the pathophysiology of heart rate control. This study uses basic physiologic principles to construct a unique model capable of describing the full time course of sympathetic and parasympathetic activity during HRR. The model is tested in a new study of 22 diverse subjects undergoing both maximal and submaximal treadmill exercise.

Prognostic value of 12-lead electrocardiogram and peak troponin I level after vascular surgery.

Objective: The aim of this investigation was to determine if the presence of ischemic electrocardiographic (ECG) changes in patients undergoing vascular surgery provides incremental prognostic information about the long-term risk of death compared with a single peak troponin level within 48 hours after surgery.

Methods: This was a retrospective analysis of 337 patients undergoing moderate-risk to high-risk vascular surgery at our institution whose ECG and biomarker data were complete. Peak cardiac troponin (cTn) I values that exceeded the upper reference limit (URL) were categorized as low-positive (+), at or exceeding the URL but less than three times the URL, or high-positive (+), at or exceeding three times the URL.

Preoperative coronary artery revascularization and long-term outcomes following abdominal aortic vascular surgery in patients with abnormal myocardial perfusion scans: a subgroup analysis of the coronary artery revascularization prophylaxis trial.

Background: Abdominal aortic operations have the highest perioperative cardiac risk. To test the impact of preoperative coronary artery revascularization (PR) in this high-risk subset, a post hoc analysis was performed in patients undergoing aortic surgery within the Coronary Artery Revascularization Prophylaxis (CARP) trial.

Methods: The study cohort was a subset of 109 CARP patients with myocardial ischemia on nuclear imaging randomized to a strategy of PR (N = 52) or no PR (N = 57) before their scheduled abdominal aortic vascular operation.

Culprit coronary lesions requiring percutaneous coronary intervention after vascular surgery often arise from in-stent restenosis of bare metal stents.

Background: The natural history of coronary artery disease (CAD) after vascular surgery is poorly defined. The aim of this study was to determine the temporal change of coronary artery lesions requiring revascularization with a percutaneous coronary intervention (PCI) after elective vascular surgery and to determine the utility of preoperative biomarkers on predicting those patients at risk for new coronary lesions.

Methods: The Coronary Artery Revascularization Prophylaxis Trial tested the long-term survival benefit of coronary artery revascularization before elective vascular surgery.

Perioperative complications after vascular surgery are predicted by the revised cardiac risk index but are not reduced in high-risk subsets with preoperative revascularization.

Background: The Revised Cardiac Risk Index (RCRI) is useful for risk stratifying patients before noncardiac operations. Among patients with documented coronary artery disease who undergo vascular surgery, it is unclear whether preoperative revascularization reduces postoperative cardiac complications in high-risk subsets defined by the RCRI.

Methods And Results: The Coronary Artery Revascularization Prophylaxis Trial was a randomized, controlled trial that tested the long-term benefit of a preoperative coronary artery revascularization before elective vascular surgery.

Usefulness of revascularization of patients with multivessel coronary artery disease before elective vascular surgery for abdominal aortic and peripheral occlusive disease.

The Coronary Artery Revascularization Prophylaxis (CARP) study showed no survival benefit with preoperative coronary artery revascularization before elective vascular surgery. The generalizability of the trial results to all patients with multivessel coronary artery disease (CAD) has been questioned. The objective of this study was to determine the impact of prophylactic coronary revascularization on long-term survival in patients with multivessel CAD.

Predictors and outcomes of a perioperative myocardial infarction following elective vascular surgery in patients with documented coronary artery disease: results of the CARP trial.

Aims: The predictors and outcomes of patients with a peri-operative elevation in cardiac troponin I above the 99th percentile of normal following an elective vascular operation have not been studied in a homogeneous cohort with documented coronary artery disease.

Methods And Results: The Coronary Artery Revascularization Prophylaxis (CARP) trial was a randomized trial that tested the benefit of coronary artery revascularization prior to vascular surgery. Among 377 randomized patients, core lab samples for peak cardiac troponin I concentrations were monitored following the vascular operation and the blinded results were correlated with outcomes.

Coronary artery bypass grafting is superior to percutaneous coronary intervention in prevention of perioperative myocardial infarctions during subsequent vascular surgery.

Background: Among patients in need of coronary revascularization before an elective vascular operation, the value of coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI) in preventing perioperative myocardial infarctions is uncertain. We hypothesized that more complete revascularization would improve outcomes after vascular surgery.

Methods: In this Veterans Affairs Cooperative trial involving 18 medical centers, 222 patients underwent elective vascular surgery after coronary revascularization.

Coronary-artery revascularization before elective major vascular surgery.

Background: The benefit of coronary-artery revascularization before elective major vascular surgery is unclear.

Methods: We randomly assigned patients at increased risk for perioperative cardiac complications and clinically significant coronary artery disease to undergo either revascularization or no revascularization before elective major vascular surgery. The primary end point was long-term mortality.

Disparate opinions regarding indications for coronary artery revascularization before elective vascular surgery.

Despite consensus guidelines, the optimal strategy for preoperative cardiac risk management among patients scheduled for major noncardiac surgery remains controversial. This study assesses current opinion about the role of preoperative coronary revascularization for patients with coronary artery disease scheduled for elective vascular surgery. Thirty-one practicing cardiologists recruited from 4 different regions reviewed case records, imaging tests, and coronary angiograms of 12 patients with coronary artery disease participating in the Coronary Artery Revascularization Prophylaxis (CARP) trial.

Assessing autonomic function by analysis of heart rate recovery from exercise in healthy subjects.

Although delayed recovery of heart rate (HR) after exercise indicates poor prognosis, the relative role of parasympathetic reactivation versus sympathetic withdrawal in controlling exercise HR recovery remains controversial. Quantifying HR recovery is difficult because the rate of recovery varies with exercise level. This study develops a model of HR recovery applicable to multiple exercise levels simultaneously.

Comparison of plasma concentrations for two amiodarone products.

Background: A generic formulation of amiodarone was recently approved by the Food and Drug Administration based on single-dose equivalence data. Because amiodarone has complex pharmacokinetic properties, a narrow therapeutic range, and a significant adverse effect profile, concern about equivalency persists.

Objective: To compare steady-state plasma concentrations of the brand-name reference product Cordarone with the AB-rated generic formulation, Pacerone, in patients exposed to both products.