The inverse Nehb J lead increases the sensitivity of Holter electrocardiographic monitoring for detecting myocardial ischemia

Randomized comparison of sevoflurane versus propofol to reduce perioperative myocardial ischemia in patients undergoing noncardiac surgery

BACKGROUND

Volatile anesthetics provide myocardial preconditioning in coronary surgery patients. We hypothesized that sevoflurane compared with propofol reduces the incidence of myocardial ischemia in patients undergoing major noncardiac surgery.

METHODS AND RESULTS

We enrolled 385 patients at cardiovascular risk in 3 centers. Patients were randomized to maintenance of anesthesia with sevoflurane or propofol. We recorded continuous ECG for 48 hours perioperatively, measured troponin T and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) on postoperative days 1 and 2, and evaluated postoperative delirium by the Confusion Assessment Method. At 6 and 12 months, we contacted patients by telephone to assess major adverse cardiac events. The primary end point was a composite of myocardial ischemia detected by continuous ECG and/or troponin elevation. Additional end points were postoperative NT-proBNP concentrations, major adverse cardiac events, and delirium. Patients and outcome assessors were blinded. We tested dichotomous end points by χ(2) test and NT-proBNP by Mann-Whitney test on an intention-to-treat basis. Myocardial ischemia occurred in 75 patients (40.8%) in the sevoflurane and 81 (40.3%) in the propofol group (relative risk, 1.01; 95% confidence interval, 0.78-1.30). NT-proBNP release did not differ across allocation on postoperative day 1 or 2. Within 12 months, 14 patients (7.6%) suffered a major adverse cardiac event after sevoflurane and 17 (8.5%) after propofol (relative risk, 0.90; 95% confidence interval, 0.44-1.83). The incidence of delirium did not differ (11.4% versus 14.4%; P=0.379).

CONCLUSIONS

Compared with propofol, sevoflurane did not reduce the incidence of myocardial ischemia in high-risk patients undergoing major noncardiac surgery. The sevoflurane and propofol groups did not differ in postoperative NT-proBNP release, major adverse cardiac events at 1 year, or delirium.

Long-term prognostic value of the preoperative 12-lead electrocardiogram before major noncardiac surgery in coronary artery disease

BACKGROUND

Knowledge of the prognostic information of preoperative 12-lead electrocardiogram (ECG) recordings in patients with coronary artery disease (CAD) undergoing noncardiac surgery is limited.

METHODS

The prognostic information derived from the preoperative ECGs of 172 CAD patients undergoing major noncardiac surgery was analyzed to determine its predictive value for long-term outcome. Primary end point was all-cause mortality; secondary end point was major adverse cardiac events (MACE) at 2 years.

RESULTS

Prevalence of ECG abnormalities was 53% for T-wave alterations; 46% for Q waves; 38% for ST deviations; and, depending on the criterion used, 2% to 19% for left ventricular hypertrophy. During follow-up, 40 (23%) patients died and 31 (18%) had MACE. After adjustment for clinical baseline findings, including current medication with beta-blockers, ST depressions (odds ratio [OR] 4.5, 95% confidence interval [CI] 1.9-10.5) and faster heart rate (HR) (OR 1.6, 95% CI 1.1-2.4, per 10 beats per minute [bpm] increase) were independent predictors of all-cause mortality. Faster HR (OR 1.7, 95% CI 1.1-2.6, per 10-bpm increase) was also an independent predictor of MACE. The predictive value of ECG variables did not change after adjustment for occurence of perioperative ischemia.

CONCLUSION

In CAD patients, the preoperative ECG contains important prognostic information and is predictive of long-term outcome independent of clinical findings and perioperative ischemia.

Predictors of long-term mortality and cardiac events in patients with known or suspected coronary artery disease who survive major non-cardiac surgery

The aim of this prospective study was to assess predictors of long-term outcome in patients with documented or suspected coronary artery disease who survive major non-cardiac surgery. The impact of patients' comorbidities, pre-operative heart rate variability and postoperative increase in cardiac troponin I on all-cause mortality and major cardiac events within 2 years was explored using multivariable logistic regression. Six of 173 patients died within the first month after surgery and were excluded from the study. Thirty-four of 167 patients (20%) died 1-24 months after surgery. Independent predictors of all-cause mortality were history of congestive heart failure (odds ratio 6.4 [95%, confidence interval 1.7-24]), pre-operatively depressed heart rate variability (odds ratio 6.4 [95%, confidence interval 1.9-21]), and age > 70 years (odds ratio 4.5 [95%, confidence interval 1.2-16]). In contrast, postoperative elevation of cardiac troponin I did not independently predict all-cause mortality or major cardiac events.

Heart rate variability and cardiac troponin I are incremental and independent predictors of one-year all-cause mortality after major noncardiac surgery in patients at risk of coronary artery disease

OBJECTIVES

The aim of this study was to determine whether perioperative measurements of heart rate variability (HRV) and cardiac troponin I (cTnI) add additional prognostic information to established risk scores for first-year mortality in patients at risk of coronary artery disease (CAD) undergoing major noncardiac surgery.

BACKGROUND

In cardiac-risk patients undergoing major noncardiac surgery, the short- and long-term prognoses are mainly influenced by perioperative cardiac complications. Heart rate variability and cTnI are important prognostic markers in patients with congestive heart failure and myocardial infarction.

METHODS

In a prospective study, 173 patients with CAD or at high risk of CAD undergoing major noncardiac surgery were followed up for one year. The main outcome measure was all-cause mortality. In addition to clinical parameters and established risk scores, HRV and cTnI were assessed perioperatively.

RESULTS

Twenty-eight (16%) patients died within one year. Multivariate logistic regression analysis revealed three findings that were independently associated with death within the first year after surgery: the revised cardiac risk index (odds ratio 6.2 [95% confidence interval 1.6 to 25], depressed HRV before induction of anesthesia (16.2 [2.8 to 94]), and elevation of cTnI on postoperative day 1 or 2 (9.8 [3.0 to 32]).

CONCLUSIONS

Depressed HRV before induction of anesthesia and elevated cTnI postoperatively are independent and powerful predictors of one-year mortality for patients at risk of CAD undergoing major noncardiac surgery and add incremental prognostic information to established risk scores that only consider preoperative information.