Vessel heterogeneity of TIMI frame count and its relation to P-wave dispersion in patients with coronary slow flow

Area of Science:

• Cardiology
• Vascular Physiology
• Electrophysiology

Background:

• Coronary slow flow (CSF) is characterized by delayed transit of contrast media through coronary arteries.
• The heterogeneity of thrombolysis in myocardial infarction (TIMI) frame count (TFC) in CSF patients is not well understood.
• The relationship between TFC heterogeneity and P-wave dispersion (PWD) in CSF remains unclear.

Purpose of the Study:

• To investigate the vessel heterogeneity of TFC in coronary arteries of patients with CSF.
• To determine the correlation between TFC heterogeneity and PWD in patients with CSF.
• To compare TFC and PWD between CSF patients and healthy controls.

Main Methods:

• A study involving 72 patients with angiographically documented CSF and 66 age- and gender-matched controls.
• Calculation of the coefficient of variation (CV) and mean TFC for three coronary vessels.
• Measurement of P-wave duration and PWD using standard electrocardiograms (ECGs).

Main Results:

• CSF patients showed significantly higher mean TFC and CV compared to controls (P<0.001).
• Maximum P-wave duration (Pmax) and PWD were significantly elevated in CSF patients versus controls (P<0.001).
• In CSF patients, Pmax and PWD correlated mildly with mean TFC and more significantly with CV (r=0.506 for PWD, P<0.001).

Conclusions:

• Increased TFC variability in coronary arteries is evident in patients with CSF.
• Vessel heterogeneity in coronary flow is closely linked to PWD in CSF patients.
• These findings suggest an association between altered coronary hemodynamics and cardiac electrical instability in CSF.