Robert L. Lobato

Perioperative outcomes of major noncardiac surgery in adults with congenital heart disease.

Background:An increasing number of patients with congenital heart disease are surviving to adulthood. Consensus guidelines and expert opinion suggest that noncardiac surgery is a high-risk event, but few data describe perioperative outcomes in this population. Methods:By using the Nationwide Inpatient Sample database (years 2002 through 2009), the authors compared patients with adult congenital heart disease (ACHD) who underwent noncardiac surgery with a non-ACHD comparison cohort matched on age, sex, race, year, elective or urgent or emergency procedure, van Walraven comborbidity score, and primary procedure code. Mortality and morbidity were compared between the two cohorts. Results:A study cohort consisting of 10,004 ACHD patients was compared with a matched comparison cohort of 37,581 patients. Inpatient mortality was greater in the ACHD cohort (407 of 10,004 [4.1%] vs. 1,355 of 37,581 [3.6%]; unadjusted odds ratio, 1.13; P = 0.031; adjusted odds ratio, 1.29; P < 0.001). The composite endpoint of perioperative morbidity was also more commonly observed in the ACHD cohort (2,145 of 10.004 [21.4%] vs. 6,003 of 37,581 [16.0%]; odds ratio, 1.44; P < 0.001). ACHD patients comprised an increasing proportion of all noncardiac surgical admissions over the study period (P value for trend is <0.001), and noncardiac surgery represented an increasing proportion of all ACHD admissions (P value for trend is <0.001). Conclusions:Compared with a matched control cohort, ACHD patients undergoing noncardiac surgery experienced increased perioperative morbidity and mortality. Within the limitations of a retrospective analysis of a large administrative dataset, this finding demonstrates that this is a vulnerable population and suggests that better efforts are needed to understand and improve the perioperative care they receive.

Genotypic and phenotypic analysis of a novel 15-base insertion occurring between codons 69 and 70 of HIV type 1 reverse transcriptase.

An HIV-1 isolate possessing a 15-base insertion between codons 69 and 70 of the reverse transcriptase (RT) gene was derived from a patient plasma sample. Investigation of the insertion sequence revealed that this mutation is an ectopic duplication of the first 15 bases of the HIV-1 envelope gene. Phenotypic analysis yielded the following increases in resistance: 371-fold to zidovudine, 84-fold to lamivudine, 32-fold to abacavir, 15-fold to stavudine, 12-fold to didanosine, and 4-fold to zalcitabine. Phenotypic studies suggested that this change does not detract from the overall fitness of the virus. Together, data from this investigation support two conclusions. First, a previously unreported mechanism exists for generating diversity in HIV-1, namely long-distance duplication of genetic material from one portion of the genome to another. Second, large insertions in this region of RT are well tolerated and can confer high levels of resistance to multiple nucleoside analogue reverse transcriptase inhibitors.

Heart transplantation with or without prior mechanical circulatory support in adults with congenital heart disease

OBJECTIVES Recent analyses establish that heart transplantation is increasing among adults with congenital heart disease (ACHD), but the effects of pretransplant mechanical circulatory support (MCS) on perioperative and post-transplant outcomes have not been examined in the ACHD population. METHODS Scientific Registry of Transplant Recipients data on all adult heart transplants from September 1987 to September 2012 (n = 47 160) were classified based on primary diagnosis codes as CHD or non-CHD and MCS or non-MCS. Demographic, procedural, outcome and survival variables were compared between MCS and non-MCS ACHD patient groups. RESULTS MCS was used in 83 (6.8%) ACHD patients compared with 8625 (18.8%) patients without CHD (P < 0.001). MCS as a fraction of ACHD transplants increased over time (P = 0.002). MCS patients spent more time on the wait list, had a higher baseline serum creatinine and were more likely to be male, status 1A, hospitalized, in the ICU and/or on a ventilator prior to transplant. However, MCS patients experienced equivalent short-term survival (30-day mortality = 10.8% in MCS vs 13.5% in non-MCS, P = 0.62) and overall survival by Kaplan-Meier analysis (P = 0.57). MCS patients had a longer post-transplant length of stay and were more likely to be transfused, but otherwise had no significant differences in adverse outcomes. CONCLUSIONS MCS is less commonly used in adult CHD patients compared with all patients undergoing heart transplant, but has been increasing over time. Within the ACHD population, patients with MCS have a higher risk profile, but except for increased transfusion rate and longer length of stay, do not experience less favourable post-transplant outcomes.

Factor VIII Inhibitor Bypass Activity and Recombinant Activated Factor VII in Cardiac Surgery

OBJECTIVE Postcardiopulmonary bypass hemorrhage remains a serious complication of cardiac surgery. Given concerns regarding adverse effects of blood product transfusion and limited efficacy of current antifibrinolytics, procoagulant medications, including recombinant factor VIIa (rFVIIa) and factor eight inhibitor bypass activity (FEIBA), increasingly have been used in managing refractory bleeding. While effective, these medications are associated with thromboembolic complications. This study compared the efficacy and risk of adverse events of rFVIIa and FEIBA in cardiac surgical patients with refractory bleeding. DESIGN This retrospective study evaluated 168 patients who underwent cardiac surgery and received either FEIBA or rFVIIa to manage postbypass hemorrhage. Demographic, clinical, and outcomes data were collected and statistical analysis performed to compare thromboembolic event rates, relative efficacy, and 30-day mortality following administration of these medications. SETTING Single university hospital. PARTICIPANTS Patients undergoing cardiac surgery. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULT Sixty-one patients received rFVIIa, and 107 received FEIBA. Demographics, surgical procedures, and preoperative anticoagulation were similar between the cohorts; however, the rFVIIa cohort had longer durations of cardiopulmonary bypass (305.1 v 243.8 min, p<0.01). There were no significant differences in the number of thromboembolic events, 30-day mortality, or rates of revision surgery. Neither group demonstrated a clear relationship between dosage and occurrence of thromboembolic events. The rFVIIa cohort received more platelets than the FEIBA cohort (3.13 v 1.67 units, p = 0.01), but transfusion rates of other blood products were similar. CONCLUSIONS This study suggests that rFVIIa and FEIBA have similar efficacy and adverse event profiles in managing intractable postbypass hemorrhage in cardiac surgical patients. Further prospective studies are required.

P-Wave Characteristics on Routine Preoperative Electrocardiogram Improve Prediction of New-Onset Postoperative Atrial Fibrillation in Cardiac Surgery

OBJECTIVE To test the hypothesis that including preoperative electrocardiogram (ECG) characteristics with clinical variables significantly improves the new-onset postoperative atrial fibrillation prediction model. DESIGN Retrospective analysis. SETTING Single-center university hospital. PARTICIPANTS Five hundred twenty-six patients, ≥ 18 years of age, who underwent coronary artery bypass grafting, aortic valve replacement, mitral valve replacement/repair, or a combination of valve surgery and coronary artery bypass grafting requiring cardiopulmonary bypass. INTERVENTIONS Retrospective review of medical records. MEASUREMENTS AND MAIN RESULTS Baseline characteristics and cardiopulmonary bypass times were collected. Digitally-measured timing and voltages from preoperative electrocardiograms were extracted. Postoperative atrial fibrillation was defined as atrial fibrillation requiring therapeutic intervention. Two hundred eight (39.5%) patients developed postoperative atrial fibrillation. Clinical predictors were age, ejection fraction<55%, history of atrial fibrillation, history of cerebral vascular event, and valvular surgery. Three ECG parameters associated with postoperative atrial fibrillation were observed: Premature atrial contraction, p-wave index, and p-frontal axis. Adding electrocardiogram variables to the prediction model with only clinical predictors significantly improved the area under the receiver operating characteristic curve, from 0.71 to 0.78 (p<0.01). Overall net reclassification improvement was 0.059 (p = 0.09). Among those who developed postoperative atrial fibrillation, the net reclassification improvement was 0.063 (p = 0.03). CONCLUSION Several p-wave characteristics are independently associated with postoperative atrial fibrillation. Addition of these parameters improves the postoperative atrial fibrillation prediction model.

Temporal Changes in Survival after Cardiac Surgery Are Associated with the Thirty-Day Mortality Benchmark

OBJECTIVE To assess the hypothesis that postoperative survival exhibits heterogeneity associated with the timing of quality metrics. DATA SOURCES Retrospective observational study using the Nationwide Inpatient Sample from 2005 through 2009. STUDY DESIGN Survival analysis was performed on all admission records with a procedure code for major cardiac surgery (n = 595,089). The day-by-day hazard function for all-cause in-hospital mortality at 1-day intervals was analyzed using joinpoint regression (a data-driven method of testing for changes in hazard). DATA EXTRACTION METHODS A comprehensive analysis of a publicly available national administrative database was performed. PRINCIPAL FINDINGS Statistically significant shifts in the pattern of postoperative mortality occurred at day 6 (95 percent CI = day 5-8) and day 30 (95 percent CI = day 20-35). CONCLUSIONS While the shift at day 6 plausibly can be attributed to the separation between routine recovery and a complicated postoperative course, the abrupt increase in mortality at day 30 has no clear organic etiology. This analysis raises the possibility that this observed shift may be related to clinician behavior because of the use of 30-day mortality as a quality metric, but further studies will be required to establish causality.

Perioperative morbidity and mortality of cardiothoracic surgery in patients with a do-not-resuscitate order

Background. Do-not-resuscitate (DNR) orders are often active in patients with multiple comorbidities and a short natural life expectancy, but limited information exists as to how often these patients undergo high-risk operations and of the perioperative outcomes in this population. Methods. Using comprehensive inpatient administrative data from the Public Discharge Data file (years 2005 through 2010) of the California Office of Statewide Health Planning and Development, which includes a dedicated variable recording DNR status, we identified cohorts of DNR patients who underwent major cardiac or thoracic operations and compared themto age- and procedure-matched comparison cohorts. The primary study outcome was in-hospital mortality. Results. DNR status was not uncommon in cardiac (n = 2,678, 1.1% of all admissions for cardiac surgery, age 71.6 ± 15.9 years) and thoracic (n = 3,129, 3.7% of all admissions for thoracic surgery, age 73.8 ± 13.6 years) surgical patient populations. Relative to controls, patients who were DNR experienced significantly greater inhospital mortality after cardiac (37.5% vs. 11.2%, p < 0.0001 and thoracic (25.4% vs. 6.4%) operations. DNR status remained an independent predictor of in-hospital mortality onmultivariate analysis after adjustment for baseline and comorbid conditions in both the cardiac (OR 4.78, 95% confidence interval 4.21–5.41, p < 0.0001) and thoracic (OR 6.11, 95% confidence interval 5.37–6.94, p < 0.0001) cohorts. Conclusions. DNR status is associated with worse outcomes of cardiothoracic surgery even when controlling for age, race, insurance status, and serious comorbid disease. DNR status appears to be a marker of substantial perioperative risk, and may warrant substantial consideration when framing discussions of surgical risk and benefit, resource utilization, and biomedical ethics surrounding end-of-life care.

Tricuspid regurgitation jet velocity suggestive of severe pulmonary hypertension.

A 73-YEAR-OLD WOMAN suffered a cardiac arrest in the emergency department waiting room. After prompt resuscitation and admission to the coronary care unit, coronary angiography showed critical stenosis of the left main and left circumflex arteries. An intra-aortic balloon pump was placed, a heparin infusion was initiated, and the patient was brought for urgent coronary artery bypass grafting. Transesophageal echocardiography revealed the unexpected finding of near-systemic right ventricular systolic pressure by tricuspid regurgitation jet velocity on continuous wave Doppler. Midesophageal 4-chamber (Fig 1), midesophageal right ventricular inflowoutflow, and transgastric right ventricular inflow (Fig 2) views revealed a moderate tricuspid regurgitation jet with maximum velocity of 4.88 m/sec, which predicts a right ventricular