Introduction: Normal blood circulation through the coronary arteries is a condition for the normal functioning of the myocardium. If a coronary artery is occluded, a heart attack occurs in the area supplied by that artery. PCI is a non-surgical technique used to treat obstructive coronary artery disease such as ischemic heart disease. Ischemic heart disease is considered a set of syndromes that arise due to myocardial ischemia. Angina pectoris means a syndrome manifested by discomfort or pressure in the chest and is caused by transient ischemia of the heart muscle. The aim of the research: The aim of the research is to analyze patients who underwent percutaneous coronary intervention, according to gender, age and indications within the time period from 01.01.2021. until 01.01.2022. years. Materials and methods: The paper used data from the medical records of Thalassotherapy Opatija and the WINBIS system. The age of the patients was compared according to their gender using the parametric T-test for independent samples (the data followed the normality of the distribution which was proven by the Kolmogorov-Smirnov test, the homogeneity of variances was confirmed by the Levene's test). Differences in the frequency of indications according to the gender of the patients were examined using the Pearson Chi-square test. The above tests were performed at the level of statistical significance of 0.05 (5%). The data were processed in the Statistica program (Version 13.5.0.17, 1984-2018 TIBCO Software Inc) Results: In Thalassotherapy Opatija, in the time period from 01.01.2021. until 01.01.2022. performed percutaneous coronary intervention in 324 patients, of whom 69.75% (n=226) were male and 30.24% (n=98) were female. The average age of the patients was 71 years. The youngest operated patient was 39 years old, and the oldest was 88 years old. Ischemic heart disease was the indication for percutaneous coronary intervention in a total of 13.89% (n=45) of cases. Angina pectoris was the indication for percutaneous coronary intervention in a total of 8.64% (n=28) of cases. Conclusion: According to the results obtained in this research, we can conclude that percutaneous coronary intervention is performed more often in elderly men. Also that ischemic heart disease is the diagnosis after which percutaneous coronary intervention is more often performed in Thalassotherapy Opatija.