https://rpubs.com/alex_istrate/605846

# 2 Special part

## 2.2 Methods

### 2.2.1 Statisitcal analysis of the data

To describe the quantitative variables, we used histograms and we calculated the arithmetic means Â±standard deviation (SD) [with 95% confidence interval (CI)], as well as the extreme and median values. For the qualitative variables, we used pie or bar charts and calculated the absolute and percentual frequencies of the formed categories.

To study the relationships between quantitative and qualitative variables, we used the T or Mann-Whitney (MW) tests if they were binary, respectively ANOVA or Kruskal-Wallis (KW) if they had more categories. We presented the p values generated by these tests as well as the means Â±SD of the groups and the difference of the means with associated 95% CI. We graphically presented the results in the form of box plots. To study the relationships between the quantitative variables we used the Spearman correlation coefficient (R), with the associated p-value and graphically presented the relations as scatter plots, on which we added the regression line. To describe the relationships between the qualitative variables we used the ChiÂ² or Fisher test and the Cramer phi or V and Odds-Ratio (OR) / Relative Risk (RR) indicators with 95% CI. We graphically presented the results in the form of pie or bar charts.

We used Microsoft Excel 2016 for database management. For all statistical analyzes and subsequent graphs we used R 3.6.3 [1]. We considered p <0.05 to be statistically significant and p <0.10 to show only a tendency towards statistical significance.

## 2.3 Results

### 2.3.1 Demographics

A total of 283 patients were included din the study, of whom 86.8% had only one intervention yet, while 10.3% had 2 interventions, 2.9% had more (up to 5).

Among unique patients, 66.4% were men. At the time of each intervention, age had values between 40.2 and 94.2 years old (median = 70) with a mean of 69.65 Â±10.6 years old. At the time of the first interention, women were significantly older then men (F:71.82 Â±10.8 years old, M: 68.90 Â±10.3 years old).

At the time of each intervention, BMI had values between 15.63 and 42.22 kg/mÂ² (median = 25.83) with a mean of 26.77 Â±4.72 kg/mÂ². BMI had a statistically significant but weak negative correlation with age (-0.27, p<0.001).

Table 1: Demographic parameters of the sample.

 Variable Details Total N= 283 Sex F 76 (33.6%) M 150 (66.4%) Age (years) Î¼ Â±SD 69.65 Â±10.6 M (min:max) 70 (40.2:94.2) BMI (kg/mÂ²) Î¼ Â±SD 26.77 Â±4.72 M (min:max) 25.83 (15.63:42.22) No. interventions 1 210 (86.8%) 2 25 (10.3%) 3+ 7 (2.9%) Î¼ Â±SD = Mean (standard deviation); M (min:max) = Median (min:max);

Figure 1: Sex distribution.

Figure 2: Number of visits.

Figure 3: Age distribution, at each intervention, colored by sex. (| mean, Â¦ median).

Figure 4: BMI distribution, at each intervention, colored by sex. (| mean, Â¦ median).

Figure 5: Correlation of BMI and age, colored by sex (Spearmanâ€™scorrelation coefficient).

### 2.3.2 Main

Most patients with an ACOMI diagnosis had stage IV (78.3%), or III (20.9%) and only 2 patients had stage IIb.

Most cases were registerd in 2019 (n=61, 23.0%) and the least were registerd in 2016 (n=18, 6.8%), 2014 (n=26, 9.8%).
264 (93.6%) interventions were successful.

Angiography was performed in 123 (46.4%) patients and coronarography in 16 (6.0%) patients. Elective or multivascular angioplasty was performed in 159 (56.2%) and 80 (28.3%) patients.

More than half of the patients (n=143, 50.5%) were not implanted stents. Only one stent was implanted in 100 patients (35.3%) and 2 or more were implanted in 40 patients (14.1%, up to 6 stents).

Table 2: Main parameters of the sample.

 Variable Details Total N= 283 ACOMI ACOMI IIB 2 (0.8%) ACOMI III 51 (20.9%) ACOMI IV 191 (78.3%) Angiography 123 (46.4%) Coronarography 16 (6.0%) Examination year 2014 26 (9.8%) 2015 51 (19.2%) 2016 18 (6.8%) 2017 47 (17.7%) 2018 62 (23.4%) 2019 61 (23.0%) Success of intervention 264 (93.6%) Number of stents 0 143 (50.5%) 1 100 (35.3%) 2 25 (8.8%) 3 6 (2.1%) 4 5 (1.8%) 5 2 (0.7%) 6 2 (0.7%) Elective angioplasty 159 (56.2%) Multivascular angioplasty 80 (28.3%) Î¼ Â±SD = Mean (standard deviation); M (min:max) = Median (min:max);

Figure 6: ACOMI diagnosis of the patients.

Figure 7: Year of examination.

Figure 8: Success of intervention.

Figure 9: Angiography and Coronarography.