Remote Postdischarge Treatment of Patients With Acute Myocardial Infarction by Allied Health Care Practitioners vs Standard Care: The IMMACULATE Randomized Clinical Trial

Abstract

Importance: There are few data on remote postdischarge treatment of patients with acute myocardial infarction.

Objective: To compare the safety and efficacy of allied health care practitioner-led remote intensive management (RIM) with cardiologist-led standard care (SC).

Design, setting, and participants: This intention-to-treat feasibility trial randomized patients with acute myocardial infarction undergoing early revascularization and with N-terminal-pro-B-type natriuretic peptide concentration more than 300 pg/mL to RIM or SC across 3 hospitals in Singapore from July 8, 2015, to March 29, 2019. RIM participants underwent 6 months of remote consultations that included β-blocker and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACE-I/ARB) dose adjustment by a centralized nurse practitioner team while SC participants were treated face-to-face by their cardiologists.

Main outcomes and measures: The primary safety end point was a composite of hypotension, bradycardia, hyperkalemia, or acute kidney injury requiring hospitalization. To assess the efficacy of RIM in dose adjustment of β-blockers and ACE-I/ARBs compared with SC, dose intensity scores were derived by converting comparable doses of different β-blockers and ACE-I/ARBs to a scale from 0 to 5. The primary efficacy end point was the 6-month indexed left ventricular end-systolic volume (LVESV) adjusted for baseline LVESV.

Results: Of 301 participants, 149 (49.5%) were randomized to RIM and 152 (50.5%) to SC. RIM and SC participants had similar mean (SD) age (55.3 [8.5] vs 54.7 [9.1] years), median (interquartile range) N-terminal-pro-B-type natriuretic peptide concentration (807 [524-1360] vs 819 [485-1320] pg/mL), mean (SD) baseline left ventricular ejection fraction (57.4% [11.1%] vs 58.1% [10.3%]), and mean (SD) indexed LVESV (32.4 [14.1] vs 30.6 [11.7] mL/m2); 15 patients [5.9%] had a left ventricular ejection fraction <40%. The primary safety end point occurred in 0 RIM vs 2 SC participants (1.4%) (P = .50). The mean β-blocker and ACE-I/ARB dose intensity score at 6 months was 3.03 vs 2.91 (adjusted mean difference, 0.12 [95% CI, -0.02 to 0.26; P = .10]) and 2.96 vs 2.77 (adjusted mean difference, 0.19 [95% CI, -0.02 to 0.40; P = .07]), respectively. The 6-month indexed LVESV was 28.9 vs 29.7 mL/m2 (adjusted mean difference, -0.80 mL/m2 [95% CI, -3.20 to 1.60; P = .51]).

Conclusions and relevance: Among low-risk patients with revascularization after myocardial infarction, RIM by allied health care professionals was feasible and safe. There were no differences in achieved medication doses or indices of left ventricular remodeling. Further studies of RIM in higher-risk cohorts are warranted.

Trial registration: ClinicalTrials.gov Identifier: NCT02468349.

Conflict of interest statement

Conflict of Interest Disclosures: Drs Chan, Chin, J. Tan, Ho, and Loh receive consultation honoraria from AstraZeneca. Drs Chan, Richards and Hausenloy receive research grant funding from AstraZeneca. Dr J. Tan reports grants from Medtronic and honorarium from Bayer, Roche Diagnostics, and Philips outside the submitted work. No other disclosures were reported.

Figures

Figure.. Enrollment, Randomization, and Follow-up

NT-pro BNP indicates N-terminal pro–b-type natriuretic peptide. aRerandomized numbers and total randomized numbers are mutually exclusive. Ten participants had to be rerandomized because of carbon11–labeled acetate quality control failure in a position emission tomography substudy. bA total of 136 participants successfully underwent remote intensive management after baseline cardiac magnetic resonance imaging. cA total of 13 participants did not receive remote intensive management because 7 participants withdrew before baseline cardiac magnetic resonance imaging and 6 had claustrophobia. dA total of 139 participants underwent standard care after baseline cardiac magnetic resonance imaging. eA total of 13 participants did not receive standard care because 8 participants withdrew before baseline cardiac magnetic resonance imaging and 5 had claustrophobia. fPrimary analysis included participants who completed both baseline and follow-up cardiac magnetic resonance imaging scans and had images that were interpretable.