Hibbert, Benjamin

OBJECTIVES: Inotropic support is commonly used in patients with cardiogenic shock (CS). High-quality data guiding the use of dobutamine or milrinone among this patient population is limited. We compared the efficacy and safety of these two inotropes among patients with low cardiac output states (LCOS) or CS. DATA SOURCES: MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were searched up to February 1, 2023, using key terms and index headings related to LCOS or CS and inotropes. DATA EXTRACTION: Two independent reviewers included studies that compared dobutamine to milrinone on all-cause in-hospital mortality, length of ICU stay, length of hospital stay, and significant arrhythmias in hospitalized patients. DATA SYNTHESIS: A total of eleven studies with 21,084 patients were included in the meta-analysis. Only two randomized controlled trials were identified. The primary outcome, all-cause mortality, favored milrinone in observational studies only (odds ratio [OR] 1.19 (95% CI, 1.02–1.39; p = 0.02). In-hospital length of stay (LOS) was reduced with dobutamine in observational studies only (mean difference –1.85 d; 95% CI –3.62 to –0.09; p = 0.04). There was no difference in the prevalence of significant arrhythmias or in ICU LOS. CONCLUSIONS: Only limited data exists supporting the use of one inotropic agent over another exists. Dobutamine may be associated with a shorter hospital LOS; however, there is also a potential for increased all-cause mortality. Larger randomized studies sufficiently powered to detect a difference in these outcomes are required to confirm these findings.

Objective Atrial fibrillation (AF) remains a highly prevalent arrhythmia with significant burden on morbidity and mortality. The impact of AF in the revascularised population remains incompletely described. Given the high prevalence of AF in the revascularised population, we sought to evaluate the incidence and prognosis in patients with pre-existing and new-onset AF following revascularisation. Methods We used the University of Ottawa Heart Institute Revascularisation Registry to identify patients who underwent revascularisation between August 2015 and March 2020, who were prospectively followed for an average of one year. We conducted a retrospective cohort study analysing the association between AF and clinical outcomes. The primary outcome of interest was 1-year major adverse cardiac events (MACE) defined as a composite of death, myocardial infarction, unplanned revascularisation and cerebrovascular accidents. Moreover, secondary outcomes include the individual components of MACE and bleeding. Results A total of 6704 patients underwent revascularisation and completed 1-year clinical follow-up. Median time to follow-up was 12.8 (IQR 11.2–15.9) months. One-year MACE occurred in 166 (21.8%) and 683 (11.5%) patients in AF and non-AF groups, respectively (adjusted HR, 1.61; 95% CI 1.29 to 2.01; p<0.0001). AF was independently predictive of 1-year mortality, myocardial infarction, unplanned revascularisation, cerebrovascular accident and bleeding. Within 1 year, 299 (4.5%) episodes of new-onset AF was observed. New-onset AF following revascularisation was also associated with 1-year MACE, mortality, myocardial infarction, cerebrovascular accident and unplanned revascularisation. Conclusions Preprocedural and new-onset AF following revascularisation remains highly predictive 1-year MACE. AF should be considered in addition to traditional risk factors for adverse outcomes following revascularisation.

Purpose of review Cardiogenic shock with significant mitral regurgitation portends a poor prognosis with limited therapeutic options. Herein, we review the available evidence regarding the patient characteristics, management, impact of transcatheter edge-to-edge repair (TEER) on hemodynamics, and clinical outcomes of patients with cardiogenic shock and mitral regurgitation. Recent findings Several observational studies and systematic reviews have demonstrated the feasibility and safety of TEER in cardiogenic shock complicated by degenerative or functional mitral regurgitation. Surgical interventions for mitral regurgitation remain limited owing to the risk profile of patients in cardiogenic shock. TEER has been studied in both degenerative and functional mitral regurgitation and remains feasible in the critically ill population. Moreover, TEER is associated with reduction in mitral regurgitation and improvement in-hospital and long-term mortality. Summary TEER remains a promising therapeutic option in cardiogenic shock complicated by significant mitral regurgitation, but additional research is required to identify patient and procedural characteristics, hemodynamic parameters, and the optimal time for intervention. Moreover, future randomized controlled trials are in progress to evaluate the potential benefit of TEER against medical management in cardiogenic shock and mitral regurgitation.

Introduction There is emerging evidence supporting the use of the radial artery (RA) as a preferred secondary conduit for coronary artery bypass grafting (CABG) as it is associated with higher rates of graft patency at 5 years when compared with saphenous vein grafts (SVG). The modified Allen’s test (MAT) is traditionally regarded as the standard of care in the assessment of ulnar artery (UA) patency prior to RA harvesting. Unfortunately, due to high false-positive rates, a substantial number of pre-CABG patients are found to have an abnormal MAT despite normal UA patency, resulting in inappropriate exclusion from RA harvesting. The SVG is generally used in its place when this occurs, resulting in potentially lower rates of long-term graft patency. Methods and analysis The CAPITAL iRADIAL-CABG trial is currently enrolling participants 18 years of age or older undergoing CABG for whom the treating physician is considering the use of an RA conduit. Eligible patients will be randomised in a 1:1 fashion to MAT or smartphone-based photoplethysmography application assessment to assess collateral palmar circulation prior to RA harvesting. The primary outcome of the trial is the use of the RA as a conduit during CABG. The primary safety outcome is postoperative palmar ischaemia as determined by clinical assessment or requirement of vascular intervention. Secondary outcomes include vascular complications, early graft failure, need for rescue percutaneous coronary intervention during the index hospitalisation and a composite cardiovascular outcome of myocardial infarction, stroke and cardiovascular death prior to discharge from hospital. A total of 236 participants are planned to be recruited. Ethics and dissemination The study was approved by the Ottawa Heart Science Network Research Ethics Board (approval number 20180865-01H). The study results will be disseminated via conference presentations and peer-reviewed publications. Trial registration number NCT03810729.

Background Recent studies have shown improved outcomes in cardiogenic shock through protocols directed toward early identification and initiation of mechanical circulatory support. However, objective therapeutic targets—based on clinical and/or laboratory data—to guide real‐time clinical decision making are lacking. Lactate clearance has been suggested as a potential treatment target because of its independent association with mortality. Methods and Results In a post hoc analysis of the DOREMI (Dobutamine Compared to Milrinone in the Treatment of Cardiogenic Shock) trial—a randomized, double‐blind, controlled trial comparing milrinone to dobutamine in the treatment of cardiogenic shock—we used prospectively collected lactate data to evaluate lactate clearance as a surrogate marker for in‐hospital mortality. In total, 82 (57.7%) patients survived to hospital discharge (survivors). In multivariate logistic regression analysis, complete lactate clearance, percentage lactate clearance, and percentage lactate clearance per hour were independently associated with survival beginning as early as 8 hours after enrollment. Complete lactate clearance was the strongest predictor of survival at all time points, with odds ratios ranging between 2.46 (95% CI, 1.09–5.55; P =0.03) at 8 hours to 5.44 (95% CI, 2.14–13.8; P <0.01) at 24 hours. Conclusions Complete lactate clearance is a strong and independent predictor of in‐hospital survival in patients with cardiogenic shock. Together with previously published data, these results further support the validity of lactate clearance as an appropriate surrogate for mortality and as a potential therapeutic target in future cardiogenic shock trials. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03207165.

Abstract Objective We sought to evaluate the association between the institutional volume of catheter‐directed thrombolysis (CDT) for pulmonary embolism and in‐hospital mortality. Background CDT is an increasingly utilized therapy in patients with intermediate/high‐risk PE. However, data on the relationship between hospital volume and clinical outcomes remain limited. Methods Patients who underwent CDT between October 1, 2015, and March 31, 2021, were identified in the Vizient Clinical Database. The primary outcome was in‐hospital mortality. Secondary outcome were major complications, length of stay, and cost. Hospitals were dichotomized into <8 and 8 cases/year following restricted cubic spline analysis. Results A total of 6741 CDT procedures at 171 hospitals were included with a median annual hospital volume of 4.1 cases (IQR = 1.9–8.3). A total of 44 hospitals (25.7%) were classified as high‐volume (8 cases/year) and performed 60.9% of all CDT cases. CDT at high‐volume centers was associated with lower in‐hospital mortality (6.0% vs. 11.3%; p < 0.0001). Stroke and bleeding rates were similar, but pulmonary complications were more frequent at low‐volume centers. CDT at high volume centers was associated with a significantly shorter length of stay and lower cost. The association between high CDT volume and in‐hospital mortality persisted after adjustment for demographics (odds ratio [OR] = 0.49, [0.41–0.58]), demographics and risk factors (OR = 0.52 [0.44–0.62]), and demographics, risk factors, and troponin elevation (OR = 0.51 [0.40–0.66]). Conclusion In a large contemporary cohort of patients undergoing CDT in the United States, low annual institutional volume of CDT was associated with higher in‐hospital mortality.

Background The randomized DOREMI (Dobutamine Compared to Milrinone) clinical trial evaluated the efficacy and safety of milrinone and dobutamine in patients with cardiogenic shock. Whether the results remain consistent when stratified by acute myocardial infarction remains unknown. In this substudy, we sought to evaluate differences in clinical management and outcomes of acute myocardial infarction complicated by cardiogenic shock (AMICS) versus non‐AMICS. Methods and Results Patients in cardiogenic shock (n=192) were randomized 1:1 to dobutamine or milrinone. The primary composite end point in this subgroup analysis was all‐cause in‐hospital mortality, cardiac arrest, non‐fatal myocardial infarction, cerebrovascular accident, the need for mechanical circulatory support, or initiation of renal replacement therapy (RRT) at 30‐days. Outcomes were evaluated in patients with (n=65) and without (n=127) AMICS. The primary composite end point was significantly higher in AMICS versus non‐AMICS (hazard ratio [HR], 2.21; 95% CI, 1.47–3.30; P =0.0001). The primary end point was driven by increased rates of all‐cause mortality, mechanical circulatory support, and RRT. No differences in other secondary outcomes including cardiac arrest or cerebrovascular accident were observed. AMICS remained associated with the primary composite outcome, 30‐day mortality, and RRT after adjustment for age, sex, procedural contrast use, multivessel disease, and inotrope type. Conclusions AMI was associated with increased rates of adverse clinical outcomes in cardiogenic shock along with increased rates of mortality and initiation of mechanical circulatory support and RRT. Contrast administration during revascularization likely contributes to increased rates of RRT. Heterogeneity of outcomes in AMICS versus non‐AMICS highlights the need to study interventions in specific subgroups of cardiogenic shock. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03207165.