European Journal of Cardiovascular Medicine

Chronic total occlusions are identified in approximately 15–20% of patients undergoing coronary angiography and are frequently associated with advanced coronary artery disease, prior myocardial infarction, and impaired left ventricular function [1,14]. Historically, CTO lesions were often managed conservatively due to low procedural success rates and higher complication risks [1,6]. However, advances in guidewire technology, microcatheters, intravascular imaging, and the hybrid CTO approach have significantly improved procedural success and safety [2,10,11,15].

Observational registries and cohort studies have consistently demonstrated improvement in angina burden, quality of life, and ventricular function following successful CTO PCI [4,7–9]. The PROGRESS-CTO registry and similar contemporary studies have reported favorable procedural success with acceptable complication rates [4]. Nonetheless, randomized trials such as DECISION-CTO and EURO-CTO have not demonstrated a clear mortality benefit of CTO PCI over optimal medical therapy, although superior symptom relief and quality-of-life outcomes were observed following revascularization [5,6].

Given these ongoing controversies, real-world data remain important to better define patient selection and clinical benefit. The present study reports contemporary outcomes of CTO PCI and contextualizes these findings within existing evidence.

Study Design and Population This was a prospective, single‑center observational study including 78 consecutive patients who underwent CTO PCI. CTO was defined as a coronary artery occlusion with TIMI 0 flow and an estimated duration greater than three months.[1,15] Baseline Assessment Baseline demographics, cardiovascular risk factors, prior revascularization history, and clinical presentation were recorded. The left ventricular ejection fraction was assessed using transthoracic echocardiography.[18] Angiographic and Procedural Characteristics Coronary angiography was performed using standard techniques. Lesion complexity was assessed using the J-CTO score, a validated tool for predicting procedural difficulty and success [3]. Procedural strategies were selected based on angiographic characteristics and operator discretion, following contemporary hybrid CTO PCI principles [2,11]. Outcomes and Follow-up Primary outcomes were change in LVEF and angina status at 12 months. Secondary outcomes included MACE, defined as cardiac death, non-fatal myocardial infarction, or target vessel revascularization, in line with definitions used in prior CTO outcome studies [9,19]. Statistical Analysis Continuous variables are presented as mean ± standard deviation and categorical variables as counts and percentages. In our study, no comparative statistical testing was performed, consistent with methodology used in similar observational CTO studies [16,20].

Baseline Clinical Characteristics

Baseline demographic and clinical characteristics are summarized in Table 1.

Table 1: Demographics and Clinical Baseline (N=78)

The study population demonstrated a high prevalence of cardiovascular risk factors, prior myocardial infarction (60.3%), and previous PCI (67.9%). Stable angina was the most common clinical presentation (71.8%).

Angiographic and Procedural Profile

Angiographic and procedural characteristics are presented in Table 2.

Table 4: Concomitant Medical Therapy (N=78)

Table 2: Angiographic and Procedural Profile (N=78)

The left anterior descending artery was the most frequently treated vessel (43.6%). Multivessel disease was present in 52.6% of patients. The mean J‑CTO score was 1.8 ± 1.0, indicating moderate lesion complexity.

Clinical Outcomes

12‑month clinical outcomes are summarized in Table 3.

Table 3: 12-Month Clinical Outcomes and Follow-up (N=78)

Follow‑up LVEF improved to 45.5 ± 4.5%, representing an absolute improvement of 5.5%. Angina relief of at least one CCS class was observed in 91.0% of patients. MACE occurred in 4 patients (5.1%).

Concomitant Medical Therapy

Guideline‑directed medical therapy was widely prescribed (Table 4), with 100% of patients receiving dual antiplatelet therapy and high utilization of statins and renin–angiotensin system inhibitors.

This real-world observational study demonstrates that CTO PCI performed using contemporary techniques is associated with substantial symptomatic improvement and recovery of left ventricular systolic function at 12 months, with a low incidence of adverse clinical events. These findings are consistent with large observational registries and multicenter experiences reported previously [4,8,9,19].

Improvement in left ventricular function observed in this cohort is likely attributable to restoration of antegrade flow to viable myocardium, particularly in patients with prior myocardial infarction and reduced baseline LVEF [7,12]. Prior studies have shown that successful CTO PCI can result in regional and global ventricular functional recovery, especially when myocardial viability is preserved [12,13].

Randomized trials, including DECISION-CTO and EURO-CTO, failed to demonstrate a reduction in mortality or myocardial infarction with CTO PCI compared with optimal medical therapy; however, both trials reported significant improvement in angina status and quality of life following CTO PCI [5,6]. These findings align with multiple meta-analyses demonstrating symptomatic benefit without consistent mortality advantage [7,16].Earlier mechanistic and technical studies describing percutaneous recanalization techniques for chronically occluded coronary arteries provided the foundation for contemporary CTO PCI strategies [17].

The mean J-CTO score of 1.8 in the present study reflects moderate lesion complexity, comparable to contemporary registries [3,4]. Procedural success and favorable outcomes observed underscore the importance of operator expertise, structured procedural strategies, and adherence to guideline-directed medical therapy [2,11,18].

Limitations

This study is limited by its single‑center, observational design and relatively small sample size. The absence of a control group limits causal inference. Functional capacity and quality‑of‑life measures were not systematically assessed. Longer‑term follow‑up is required to evaluate durability of clinical benefit.

In this real‑world cohort, CTO PCI was associated with significant improvement in angina and left ventricular function and a low rate of adverse events at 12 months. CTO PCI remains an effective revascularization strategy in appropriately selected patients when performed with contemporary techniques. Conflict of interest: None Funding: None

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