CV IMAGING TEAM Fr. L: Drs. Debbie Lyn Udarbe-Bautista, Edward-Bengie Magsombol, Elmer Jasper Llanes, Maria Helga Sta. Maria, Justine Iris Yap, Alinaya Cordero, Christian Michael Pawhay
MANILA — Locating blockages, assessing narrowing, and fixing pipes have been the primary objectives in managing stable coronary artery disease and heart failure (HF) throughout the years.
However, leading specialists in cardiovascular imaging session (CT-10) revealed a definitive paradigm shift during a session on May 28, 2026 at the Philippine Heart Association (PHA) PHA 56th Annual Convention and Scientific Meeting.
The shift begins an era of multi-modality functional imaging, direct myocardial tissue characterization, and advanced software metrics capable of tracking the earliest stages of vascular disease.
Redefining the ischemic movement
In his presentation, St. Luke’s Medical Center Nuclear Cardiology Head Dr. Edward-Bengie Magsombol highlighted how Myocardial Perfusion Imaging (SPECT and PET MPI) provides crucial diagnostic and prognostic data that simple stress tests and structural evaluations miss.
He reminded clinicians of the ischemic cascade—the predictable chain of events that occurs when a coronary artery is obstructed.
Perfusion abnormalities manifest long before a patient experiences systolic or diastolic disruption (detectable by echocardiography) or electrocardiographic ST-wave changes (picked up during a standard treadmill stress test).
"Nuclear perfusion imaging acts as the definitive gatekeeper for the cardiac catheterization laboratory," he said.
"By identifying functional ischemia early and accurately separating low-risk from high-risk cohorts based on the actual size and severity of the perfusion defect, we avoid unnecessary, highly invasive diagnostic angiograms," he added.
Magsombol also emphasized the clinical value of quantitative coronary flow reserve (CFR) via PET imaging and a superior sensitivity of 91 percent.
PET's absolute measurement of myocardial blood flow can detect microvascular dysfunction and localized vessel stress up to a year before a distinct anatomical lesion fully matures.
Bypassing the "calcium blooming" barrier
Philippine Lipedema and Atherosclerosis Society President Dr. Elmer Jasper Llanes introduced the clinical audience to the mechanics of Photon Counting Detector CT (PCD-CT), a hardware upgrade currently transforming traditional scanning limitations.
Standard CT machines rely on Energy Integrating Detectors (EID), which convert incoming X-ray photons into visible light via a scintillator before an underlying sensor translates that light into an electrical signal.
PCD-CT eliminates the middle step entirely. By passing X-ray photons directly through semiconductors like cadmium telluride, the machine measures the exact energy level of every single photon, translating them directly into electrical pulses.
This allows for an ultra-high spatial resolution down to 0.2 mm; the virtual removal of calcified artifact overlays, giving a pristine view of the true arterial lumen; virtual non-iodine (VNI) imaging, a software post-processing capability that mathematically subtracts contrast dyes (making physicians calculate a coronary calcium score directly from a single contrast scan).
Llanes noted that integrated machine learning software can now accurately map High-Risk Plaque (HRP) profiles—such as low-attenuation necrotic cores, positive remodeling, and the "napkin-ring sign"—and that advanced fractional flow reserve metrics (CT-FFR) increase the predictive accuracy of future major adverse cardiac events (MACE) six fold.
Reading the geometric scar patterns
For patients presenting with advanced HF, distinguishing between ischemic and non-ischemic dilated cardiomyopathy (NIDCM) is vital due to vastly different long-term survival rates.
PHA Southern Tagalog Chapter Cardiovascular Imaging Council Chair Dr. Maria Helga Sta. Maria detailed how cardiac magnetic resonance (CMR) imaging, specifically through late gadolinium enhancement (LGE), provides definitive tissue characterization.
Beyond tracking ischemic damage, Dr. Sta. Maria warned that the specific geometric pattern of LGE in non-ischemic patients dictates their sudden cardiac death (SCD) risk.
While a general presence of fibrosis elevates risk, a ring-like LGE pattern circling the ventricular wall portends a highly malignant course, independent of whether the total scar mass is above or below 5%.
Comprehensive molecular profiling links this specific ring-like configuration to aggressive underlying genetic mutations, including filaminopathies (Filamin C mutation - 61 percent) and arrhythmogenic cardiomyopathy (35 percent).
By moving from simple qualitative assessments to quantitative tracking of total myocardial fibrosis, the hazard ratio for predicting annual cardiac events increases from 2.01 to 3.58, vastly improving clinical management.
Bridging the Equity Gap in Pediatric Care
While advanced multimodality imaging thrives in well-funded tertiary hubs, applying these techniques to pediatric populations and Grown-Up Congenital Heart Disease (GUCH) patients in a developing nation brings a separate set of systemic hurdles.
University of the Philippines-Philippine General Hospital Advanced Pediatric Cardiovascular Imaging Lead Consultant Dr. Justine Iris Yap addressed the realities of managing complex congenital cases in resource-limited environments.
Yap noted that hardware availability is rarely the true roadblock in low- and middle-income countries (LMICs); rather, the true bottleneck lies in a severe shortage of specialized human infrastructure.
Most local MRI technologists are entirely untrained in complex congenital heart disease sequences, and there is an acute deficit of certified congenital readers nationwide.
Institutional silos further complicate care. Pediatric sedation often costs more than the scan itself, which drives families to decline care due to immediate financial barriers.
Yap said the system can provide cost-effective pre-operative risk stratification, pulling more children safely toward life-saving surgeries through decentralized deployment of standard cardiac CT at the regional level, and centralized and highly-specialized pediatric CMR hubs.
