Same-Day FAST-HF CMR + Biomarker & Adherence Pathway: Faster Decisions, Higher GDMT Uptake, and Fewer 90-Day Events in a Middle East Single-Center Cohort

Abstract

Background & Purpose: Access delays worsen HF outcomes. We implemented an integrated, same-day pathway combining 10-minute FAST-HF CMR (single-shot cine, dark-blood PSIR-LGE, native T1), point-of-care NT-proBNP/hs-troponin, and a pharmacist-led adherence bundle (protocolized GDMT orders, WhatsApp reinforcement, refill tracking).

Methods: Interrupted time-series with inverse probability of treatment weighting (IPTW). Adults referred for HF aetiologic assessment; exclusions: cardiogenic shock, eGFR <20 mL/min/1.73m², active myocarditis requiring admission. Pre vs Post (two 24-week epochs, seasonal match). Primary: 90-day composite (all-cause death or HF readmission). Secondary: referral-to-report time, time-to-decision, GDMT initiation at discharge, adherence (PDC ≥80% at 90 days), 30-day NT-proBNP change. Safety: AKI (KDIGO ≥2), ED revisits.

Results: N=620 referrals (298 pre; 322 post), age 63±12, 37% female, LVEF 36±9%. Access improved: referral-to-report 5.0→1.8 days (p<0.001), time-to-decision 13→4 days (p<0.001), same-day diagnosis 9%→61%. Throughput 21→33 scans/week (p<0.001). NT-proBNP reduction at ~30 days −16% vs −29% (p=0.011). GDMT at discharge increased: SGLT2i 49%→73% (IPTW aOR 2.39, 95%CI 1.72–3.35), MRA 44%→62% (aOR 1.94, 1.40–2.70). Adherence improved (PDC ≥80%: 52%→68%; aOR 1.88, 1.34–2.64). Primary endpoint: 22%→15%; aHR 0.71 (95%CI 0.54–0.95, p=0.019). Safety unchanged (AKI ≥2 3.1% vs 3.4%, p=0.82; ED revisits similar).

Conclusions: A same-day imaging–biomarker–adherence pathway anchored by FAST-HF CMR is feasible and associated with faster diagnosis, higher GDMT uptake, better adherence, improved NT-proBNP, and fewer 90-day events, without safety trade-offs.