Key Points:
- The burden of coronary artery disease (CAD) is high in South Asia, but challenges are present with time-sensitive cardiac care, as evidenced within Karachi, Pakistan (population: >23 million)
- This study deployed portable chest pain units (CPUs) across Karachi to enhance access to primary percutaneous coronary intervention (PCI) to evaluate CPUs’ effect on primary PCI access
- CPUs (complete with cardiologist, crash cart, and prompt evaluation and ECG) coincided with substantial annual increase (16-20%) in primary PCI volume with significantly reduced ischemic time
- Results from this positive study of standalone CPUs may have ramifications for acute MI care in densely populated LMICs, given CPUs’ demonstrable scalability and cost-effectiveness
South Asia has the highest burden of CAD globally with high rates of acute MI (AMI), even occurring in individuals younger than 40 years old. Within South Asia, Pakistan has the highest rate of ischemic heart disease (IHD) mortality and disability adjusted life-years (DALYs). One significant factor contributing to this epidemic is limitations on timely access to primary PCI. Notably, the Government of Sindh approved a program in 2016 offering free primary PCI, doubling the rate of primary PCI from 1500 per year prior to more than 4000 cases in 2016. Access to primary PCI is very challenging in this setting given major traffic issues and emergency room overcrowding. In Karachi, Pakistan, a city of over 23 million, efforts were made to establish stand-alone portable chest pain units (CPUs) across the city in order to expedite evaluation and referral of AMI patients to the local National Institute of Cardiovascular Diseases (NICVD), currently the world’s largest primary PCI center.
Multiple CPUs were strategically deployed throughout Karachi based on population density. From 2017 to 2023, 915,564 patients were evaluated for chest pain. 33.5% (306,794) were found to have a primary cardiac etiology (vs non-cardiac), 24% (223,120) were referred for primary PCI, and 2% of all evaluated (19,580) were found to have a STEMI. Among the STEMI patients, 81% were male, median age was 56 years old (IQR 50-65), and cardiogenic shock (Killip class III or IV) was observed in 1108 patients (5.66% of the STEMI cohort).
Regarding ischemic time outcomes, median first medical contact to device time was 100 minutes (IQR 80-135), median door to balloon time was 84 minutes (IQR 60-125) for patients presenting directly to NICVD ED, and median total ischemic time (TIT) was 232 minutes (IQR 172-315). The presence of CPUs (3 PCUs in 2017 to 18 PCUs in 2023) coincided with the increased caseload of primary PCI with an annual growth rate ranging from 16% to 20% and total primary PCI volume over 9000 by 2023.
The authors present a novel model of acute chest pain and MI care in a densely populated LMIC. These units were strategically available in areas where road access was difficult, removing barriers to swift diagnosis and triage. Given the substantial area covered and large population served, these results demonstrate scalability and may be instructive for other densely populated LMICs where acute cardiac care is challenging. Furthermore, the geographical distribution of CPUs ensures each region is within 120 minutes of a primary PCI facility, thereby promoting equitable healthcare access. With such an approach serving as a possible model of cardiac care within resource constraints, the authors conclude that such an approach requires collaboration between public bodies, healthcare professionals, and the local community in order to improve global healthcare systems.