Examining the Pre- and Post-percutaneous Coronary Intervention Blood Pressure Variability Using Ambulatory Blood Pressure Monitoring in Patients with Stable and Unstable Coronary Artery Disease

Introduction The World Health Organization has drawn attention to the fact that coronary artery disease (CAD) is our modern "epidemic." Nowadays, sudden death during sleep has become prevalent due to a lack of oxygen supply to the heart. CAD causes more deaths and disabilities and incurs greater economic costs than any other illness in the developed world. The prevalence of cardiovascular disorders and heart disease is on the rise in India. Hypertension is one of the leading risk factors for all cardiovascular diseases. This study aims to compare blood pressure variability before and after percutaneous coronary intervention (PCI), using ambulatory blood pressure monitoring (ABPM) in patients with stable and unstable CAD. Materials and methods This prospective observational study was conducted among 52 patients with stable and unstable CAD, admitted to the medicine department, who required PCI at a tertiary care hospital. Before and after PCI, the same antihypertensive drugs were orally administered. ABPM was performed before PCI and one day after PCI. ABPM was conducted every 30 minutes during the day and every 60 minutes during the night over a 24-hour period using a mobil-o-graph (IEM, Germany). The results of the observed parameters were analyzed using the HMS Client-Server 4.0 system (Informer Technologies, Inc., Los Angeles, USA). The collected data were analyzed using SPSS Statistics version 21.0 software (IBM Corp. Released 2012. IBM SPSS Statistics for Windows, Version 21.0. Armonk, NY: IBM Corp.). Results Out of 52 patients, 28 (53.8%) had stable CAD and 24 (46.2%) had unstable CAD. The mean age of patients with stable and unstable CAD was 56.64±9.44 and 57.04±12.36 years, respectively. The majority of patients with stable (67.9%) and unstable CAD (62.5%) were males. Various other variables were considered, such as lipid profile, blood sugar, cardiac troponin-I, and medical history, including hypertension and type 2 diabetes mellitus. Among stable CAD patients, a comparison between pre- and post-PCI systolic blood pressure (SBP) did not show a significant difference in all SBP measurements (p>0.05). However, the mean diurnal index was significantly lower following PCI compared to before PCI (p=0.019). Among unstable CAD patients, a comparison between pre- and post-PCI SBP showed a significant change in peak daytime, average daytime, and diurnal index (p<0.05). For all other SBP measurements, the difference between pre- and post-PCI measurements was not statistically significant (p>0.05). In patients with stable CAD, a statistically significant change in diastolic blood pressure (DBP) following PCI was observed for peak daytime, peak nighttime, and average nighttime values. In contrast, for patients with unstable CAD, a statistically significant change in DBP following PCI was observed for peak daytime, peak nighttime, and minimum daytime values (p<0.05). Statistically, post-PCI, there was no significant difference between the two groups for SBP and DBP measurements (p>0.05). Additionally, there was no significant difference between the two groups pre- and post-PCI in the pattern of dipping. Conclusion A comparison of the ABPM before and after PCI showed that, within 48 hours post-PCI, the ambulatory blood pressure indicators did not differ statistically from those before PCI.