PCI VS CABG for patients with CTO: Contemporary techniques and outcome-single center experience

CTOs are common findings on coronary arteriograms [1]. CTOs were defined as 100% coronary occlusion present for at least three months and found in almost 20% of all angiograms of patients with angina. The choice of therapy for patients undergoing coronary angiography and found to have CTOs was studied in The Canadian Multicenter Chronic Total Occlusions Registry [2]. Almost half the patients with CTOs were treated medically, and 25% underwent CABG (CTOs bypassed in 88%). PCI was performed in 30%, with a 70% success rate. While more patients with CTOs have historically been treated with CABG than PCI, technical advancements in PCI of CTOs may be expected to drive more patients with CTOs towards being treated with PCI [3].

The literature reveals that CTOs are more often treated with CABG than PCI [4]. This has been recently confirmed in the SYNTAX registry and trial [5]. However, the literature on the surgical outcome of CTO's is quite limited. CABG is a treatment for angina, and while limited, the published data suggest that CABG for CTOs reduces angina. However, the only randomized trial data is from a small subgroup in SYNTAX, finding more successful CTO revascularization with CABG than PCI. Non-randomized data from SYNTAX also show that CTO patients with complete revascularization have fewer events than patients with incomplete revascularization.

Study Design and Patient Data
This retrospective cohort study was coted between Dec 2016 till Dec 2019; the heart team diagnosed 455 patients CTO. The studied groups of patients included left anterior descending occluded according to CTO criteria; those patients were 159 patients. Some of them were deemed surgical candidates based on risk stratification (EUROSCORE) and accepted for surgical coronary revascularization, others who were still symptomatic were offered CTO/PCI, and the rest received guidelines directed medical therapy; all patients who were selected for this study were evaluated based on SYNTAX and EUROSCORE All preoperative, in-hospital, and post-discharge data were collected from the medical records. Definitions were obtained from STS definitions; for example, a Recent myocardial infarction was defined as a myocardial infarction that occurred 1 to 7 days before surgery. Old myocardial infarction was described as a myocardial infarction that occurred more than seven days before surgery. Perioperative myocardial infarction (PMI) was defined as new electrocardiographic or echocardiographic changes with creatine kinase MB more than 100 ng/ml.
The Institutional Review approved this study. Board National Heart Institute, consent was waived.

Statistical Analysis
Statistical analyses were performed using IBM SPSS Statistics 23 software (IBM Corp, Armonk, NY). Normally distributed continuous variables are expressed as the mean _ SD, and skewed continuous variables are defined as the median with the range. Non-parametric variables are expressed as frequencies and percentages. Differences with p values of less than .05 were considered statistically significant.

Results
Retrospective observational At NHI between December 2016-December 2019. Including 159 patients with CTO and CCS. The decision for revascularization was as per the heart team's decision after reviewing patient characteristics, risk factors, anatomical complexity, and surgical risk. 130 patients were advised for CABG, and 29 for PCI-CTO.

Patients' characteristics
The preoperative characteristics of the studied groups showed non-significant differences in the prevalence of Diabetes Miletus, Hypertension, Dyslipidemia, COPD, Cerebrovascular disease, Renal Impairment, Peripheral vascular disease, While the differences were significant regarding the prevalence of smoking and heart failure among both groups. These data are illustrated in

Discussion
The heart team decided more toward CABG for patients with a higher SYNTAX score, 3 VD, longer CTO segments, and a higher number of CTO lesions. Heart team decision was more toward PCI in patients with higher EURO scores and history of CVA. The procedural time was significantly longer in CABG. Hospital stay was longer with CABG.
Contemporary techniques were commonly used in both strategies (LIMA, BITA, off-pump), (Antegrade and retrograde recanalization in PCI with a failure rate of 13%. Both techniques were associated with significant relief of angina. CABG was associated with a higher possibility of having no or minimal angina at one year (P<0.001).
One year MACE was numerically higher in the PCI group. Repeated revascularization was numerically higher in the PCI group.

Conclusion
In patients with moderate or high Complex anatomy and CTO, surgical or percutaneous revascularization is feasible. CABG is more effective in angina relief. PCI is associated with a shorter hospital stay and a higher possibility of repeated revascularization.