Association of Blood Pressure Variability with Contrast Nephropathy in STEMI Patients Undergoing Primary PCI.

Background: Cardiovascular disease, particularly ST-segment elevation myocardial infarction (STEMI), continues to be a leading cause of death worldwide despite advances in treatment options. Contrast-induced nephropathy (CIN) increases the risk of morbidity and mortality after percutaneous coronary intervention (PCI) in STEMI patients. Blood pressure variability (BPV), defined as fluctuations in blood pressure (BP) over time, has been associated with cardiovascular events, stroke, target organ damage and renal dysfunction independently of BP levels. The relationship between BPV and CIN is unknown. Methods: This prospective study investigated the relationship between invasively measured short-term BPV and CIN in haemodynamically stable STEMI patients undergoing PCI. In 220 patients, BP was monitored through the femoral sheath for six hours after PCI, and systolic and diastolic standard deviation (SD), average real variability (ARV) and delta parameters were calculated using universal formulae. Results: The results indicated a significant association between short-term BPV, especially systolic BPV, and the development of CIN (p < 0.01). In particular, systolic SD [odds ratio (OR): 1.055, 95% confidence interval (CI) 1.003-1.110, p = 0.04] and systolic ARV (OR: 1.084, 95% CI 1.011-1.162, p = 0,02) emerged as independent predictors of CIN. Conclusions: Our study demonstrated that intra-arterially measured short-term BPV was associated with the development of CIN in STEMI patients. Notably, systolic SD and systolic ARV were independent predictors of CIN, which may be of clinical importance for early diagnosis and prevention. These results suggest that BPV may be an indicator of CIN risk, and further large-scale randomised trials are warranted to clarify this relationship.