Successful Coronary Chronic Total Occlusion Percutaneous Coronary Intervention Research Articles

Long-Term Outcomes of Successful Recanalization Compared With Optimal Medical Therapy for Coronary Chronic Total Occlusions in Patients With and Without Left Ventricular Systolic Dysfunction.

Background: The number of coronary chronic total occlusion (CTO) patients with left ventricular (LV) systolic dysfunction is significant, but the clinical outcomes of these patients are rarely reported. The present retrospective cohort study aimed to investigate the long-term outcomes of successful recanalization vs. optimal medical therapy (MT) for CTOs in patients with preserved and impaired LV systolic function.Methods: A total of 1,895 patients with CTOs were stratified according to LV function. Of these, 1,420 patients (74.9%) with LV ejection fraction (LVEF) >45% and 475 patients (25.1%) with LVEF ≤45% were treated with optimal MT or successful CTO percutaneous coronary intervention (PCI). A 1:1 propensity score matching (PSM) was conducted to reduce the impact of potential confounding on the outcomes. The primary outcome was the frequency of major adverse cardiac events (MACEs).Results: Throughout a 2.6-year follow-up and after adjusting for confounders, among patients with preserved LV function, successful CTO PCI was associated with reduced incidence of MACE (14.2 vs. 23.9%, adjusted HR 0.63, 95% CI 0.48–0.83, p = 0.001) compared to MT. There was no significant difference in MACE occurrence (29.6 vs. 28.9%, adjusted HR 1.05, 95% CI: 0.71–1.56, p = 0.792) between successful recanalization and MT in patients with LV systolic dysfunction. The primary outcome among patients with impaired and preserved LV systolic function after PSM was similar to that from earlier findings before PSM was conducted. A significant interaction between LV function and therapeutic strategy for MACE was observed (interaction p = 0.038).Conclusions: Compared to MT alone for management of patients with CTOs, successful CTO PCI may reduce the risk of MACE in patients with preserved LV systolic function, but not in patients with LV dysfunction.

Impact of Renal Function on Long-Term Clinical Outcomes in Patients With Coronary Chronic Total Occlusions: Results From an Observational Single-Center Cohort Study During the Last 12 Years.

Background: The number of coronary chronic total occlusion (CTO) patients with renal insufficiency is huge, and limited data are available on the impact of renal insufficiency on long-term clinical outcomes in CTO patients. We aimed to investigate clinical outcomes of CTO percutaneous coronary intervention (PCI) vs. medical therapy (MT) in CTO patients according to baseline renal function.Methods: In the study population of 2,497, 1,220 patients underwent CTO PCI and 1,277 patients received MT. Patients were divided into four groups based on renal function: group 1 [estimated glomerular filtration rate (eGFR) ≥ 90 ml/min/1.73 m2], group 2 (60 ≤ eGFR <90 ml/min/1.73 m2), group 3 (30 ≤ eGFR <60 ml/min/1.73 m2), and group 4 (eGFR <30 ml/min/1.73 m2). Major adverse cardiac event (MACE) was the primary end point.Results: Median follow-up was 2.6 years. With the decline in renal function, MACE (p < 0.001) and cardiac death (p < 0.001) were increased. In group 1 and group 2, MACE occurred less frequently in patients with CTO PCI, as compared to patients in the MT group (15.6% vs. 22.8%, p < 0.001; 15.6% vs. 26.5%, p < 0.001; respectively). However, there was no significant difference in terms of MACE between CTO PCI and MT in group 3 (21.1% vs. 28.7%, p = 0.211) and group 4 (28.6% vs. 50.0%, p = 0.289). MACE was significantly reduced for patients who received successful CTO PCI compared to patients with MT (16.7% vs. 22.8%, p = 0.006; 16.3% vs. 26.5%, p = 0.003, respectively) in group 1 and group 2. eGFR < 30 ml/min/1.73 m2, age, male gender, diabetes mellitus, heart failure, multivessel disease, and MT were identified as independent predictors for MACE in patients with CTOs.Conclusions: Renal impairment is associated with MACE in patients with CTOs. For treatment of CTO, compared with MT alone, CTO PCI may reduce the risk of MACE in patients without chronic kidney disease (CKD). However, reduced MACE from CTO PCI among patients with CKD was not observed. Similar beneficial effects were observed in patients without CKD who underwent successful CTO procedures.

Prognostic impact of collaterals in patients with a coronary chronic total occlusion: A meta-analysis of over 3,000 patients.

To assess the prognostic implications of the degree of coronary collaterals on outcomes in patients with a CTO. Coronary chronic total occlusions (CTO) are identified frequently in patients undergoing coronary angiography and have been associated with poorer prognosis. Whether the degree of coronary collaterals, the hallmark of CTOs impacts prognosis, is unknown. A search of EMBASE, MEDLINE, and Cochrane Library was conducted to identify studies reporting on coronary collaterals and risk of all-cause mortality, acute myocardial infarction (AMI) and successful percutaneous coronary intervention (PCI). Patients with Rentrop grade 0 or 1 collaterals were defined as poor collaterals, while Rentrop grade 2 or 3 were defined as robust collaterals. Twelve studies with a total of 3,369 were included. Patients with robust collaterals did not have lower rates of AMI (OR: 0.89, 95%CI: 0.39-2.04) or lower rates of all-cause mortality (OR: 0.81, 95% CI: 0.42-1.58), however were more likely to have successful PCI (OR: 4.04, 95%CI: 1.10-14.85). The presence of robust collaterals is not associated with lower rates of AMI or mortality, but does increase the likelihood of successful CTO PCI. These results have importance implications with respect to the indications for CTO PCI as well as selecting appropriate patients to undergo the procedure.

Recovery of Absolute Coronary Blood Flow and Microvascular Resistance After Chronic Total Occlusion Percutaneous Coronary Intervention: An Exploratory Study.

BackgroundThis study aimed to investigate longitudinal physiological changes in the recanalized coronary chronic total occlusion (CTO) vessel and its dependent myocardium after successful percutaneous coronary intervention (PCI).Methods and ResultsIn this pilot study, 25 patients scheduled for elective CTO PCI with viable myocardium and angiographically visible collaterals were included. Absolute coronary blood flow and absolute microvascular resistance were measured invasively using continuous thermodilution. Measurements were performed immediately after successful CTO PCI and at short‐term follow‐up. In a subgroup of patients, physiological measurements were performed at the predominant donor vessel before CTO PCI, immediately afterwards, and at follow‐up. Absolute coronary blood flow in the recanalized CTO artery increased from 148±53 mL/min immediately after PCI to 221±77 mL/min at follow‐up (P<0.001). In agreement, absolute resistance in the myocardial territory perfused by the CTO artery, decreased from 545±255 Wood units immediately after the procedure to 387±128 Wood units at follow‐up (P=0.014). There were no significant changes in the absolute coronary blood flow and resistance in the predominant donor between baseline and follow‐up. Positive remodeling of the distal CTO vessel with an increase in lumen diameter was observed.ConclusionsAfter successful CTO PCI, blood flow in the recanalized artery and microvascular function of the dependent myocardium are not immediately normal but recover over time.

Echocardiographic assessment of left ventricular function recovery post percutaneous coronary intervention of chronic total occlusions in patients with low and mid-range left ventricular ejection fractions.

Coronary chronic total occlusion (CTO) is a frequent condition encountered in cardiac catheterization laboratory with a prevalence of about 20%. Through literature, data are scarcely reported regarding the left ventricular (LV) function recovery post CTO percutaneous coronary intervention (PCI) in patients with low (<40%) and mid-range (40%-49%) LV ejection fraction (LVEF). The aim of this study was to assess the echocardiographic outcomes of CTO patients with low and mid-range LVEF successfully revascularized at 6-month follow-up. This prospective study included 75 patients with at least one CTO of an epicardial coronary artery proved by previous diagnostic coronary angiography with PCI attempt indication, and successfully revascularized. They were equally divided according to LVEF into three groups, and echocardiographic remodeling indices were assessed at baseline and 6months post PCI. Our study showed significant improvement of LVEF, S-wave velocity by tissue doppler imaging (TDI), LV wall-motion score (LVWMS), and LV systolic sphericity index (LVSIS) 6months post CTO PCI in low LVEF group, and a significant improvement in LVEF, S-wave velocity, and LVWMS in mid-range LVEF group (P<.05). The delta change in LVEF was significantly more in low LVEF group, compared to the other two groups (F=4.739, P<.05). Successful CTO PCI in patients with low and mid-range LVEF is associated with significant improvement of LVEF and other indices of myocardial remodeling after 6months of follow-up.

Meta‐analysis of the impact of successful chronic total occlusion percutaneous coronary intervention on left ventricular systolic function and reverse remodeling

We sought to examine the impact of coronary chronic total occlusion (CTO) percutaneous coronary intervention (PCI) on left ventricular (LV) function. We performed a systematic review and meta-analysis of studies published between January 1980 and November 2017 on the impact of successful CTO PCI on LV function. A total of 34 observational studies including 2735 patients were included in the meta-analysis. Over a weighted mean follow-up of 7.9 months, successful CTO PCI was associated with an increase in LV ejection fraction by 3.8% (95%CI 3.0-4.7, P < 0.0001, I2 = 45%). In secondary analysis of 15 studies (1248 patients) that defined CTOs as occlusions of at least 3-month duration and reported follow-up of at least 3-months after the procedure, successful CTO PCI was associated with improvement in LV ejection fraction by 4.3% (95%CI [3.1, 5.6], P < 0.0001). In the 10 studies (502 patients) that reported LV end-systolic volume, successful CTO PCI was associated with a decrease in LV end-systolic volume by 4 mL, (95%CI -6.0 to -2.1, P < 0.0001, I2 = 0%). LV end-diastolic volume was reported in 9 studies with 403 patients and did not significantly change after successful CTO PCI (-2.3 mL, 95%CI -5.7 to 1.2 mL, P = 0.19, I2 = 0%). Successful CTO PCI is associated with a statistically significant improvement in LV ejection fraction and decrease in LV end-systolic volume, that may reflect a beneficial effect of CTO recanalization on LV remodeling. The clinical implications of these findings warrant further investigation.

The impact of successful revascularization of coronary chronic total occlusions on long-term clinical outcomes in patients with non-ST-segment elevation myocardial infarction.

The purpose of this study was to assess the long-term clinical impact of revascularization of coronary concomitant coronary chronic total occlusion (CTO) in patients with Non-ST-segment elevation myocardial infarction (NSTEMI). CTO is associated with poorer prognosis in patients with NSTEMI. The evidence of revascularization of CTO in patients with NSTEMI is still conflicting. Consecutive patients with NSTEMI and CTO who underwent percutaneous coronary intervention (PCI) within 72 h of admission from 2006 to 2015 were retrospectively recruited and analyzed. A total of 967 patients underwent PCI for NSTEMI. Among them, 106 (11%) patients had concomitant CTO and were recruited for analysis. CTO lesions were revascularized successfully in 67 (63.2%) patients (successful CTO PCI group), while the CTO in the remaining 39 patients were either not attempted or failed (No/failed CTO PCI group). The 30-day cardiac death and major adverse cardiac events (MACE) were significantly lower in the successful CTO PCI group (both cardiac death and MACE were 3% vs 30%, P < 0.001, respectively). A landmark analysis set at 30th day for 30-day survivals was performed. After a mean of 2.5-year follow-up, the long-term cardiac death was still significantly lower (16.9% vs 42.3%, P < 0.001), whereas the MACE showed a trend toward lower incidence (26.2% vs 40.7%, P = 0.051) in the successful CTO PCI group. In multivariate Cox regression analysis, successful revascularization of CTO is an independent protective predictor for long-term cardiac death (HR 0.310, 95% CI, 0.109-0.881, P = 0.028) in all population and in propensity-score matched cohort (P = 0.007). Successful revascularization of CTO was associated with reduced risk of long-term cardiac death in patients with NSTEMI and concomitant CTO.

Survival after percutaneous coronary intervention for chronic total occlusion in elderly patients.

Few data are available on outcomes of percutaneous coronary intervention (PCI) for coronary chronic total occlusions (CTO) in very elderly patients in the drug-eluting stent (DES) era. We aimed to investigate long-term survival in a single-centre cohort of elderly patients following CTO PCI using DES. A total of 2,002 consecutive patients who underwent PCI of a CTO at our centre between January 2005 and December 2013 were followed for a median of 2.6 years (interquartile range 1.1-3.1 years). Four hundred and nine (409) patients were older than 75 years. The absolute reduction in all-cause mortality by successful CTO PCI was numerically greater in elderly patients as compared to younger patients (22.1% vs. 7.2% at three years). In multivariate models, successful CTO PCI was significantly associated with improved survival in both elderly (adjusted hazard ratio [HR] 0.58, 95% confidence interval [CI]: 0.39 to 0.87; p=0.009) and younger patients (adjusted HR 0.59, 95% CI: 0.40 to 0.86; p=0.006). In the DES era, elderly patients (≥75 years) derive a similar survival benefit from successful CTO PCI to younger patients. These findings suggest that CTO PCI, when indicated, should not be withheld from the elderly.

Recanalization of Chronic Total Occlusions in Patients With Previous Coronary Bypass Surgery and Consideration of Retrograde Access via Saphenous Vein Grafts

The prevalence of native coronary chronic total occlusions (CTOs) after coronary artery bypass grafts (CABGs) is higher than in non-CABG population. We examined outcomes of CTO percutaneous coronary intervention (PCI) post-CABG versus without CABG. Then, we looked at feasibility and outcomes of retrograde CTO PCI via patent or occluded saphenous vein graft. We compared patient and procedural characteristics of 470 CTO cases treated from January 2010 to December 2015 depending on history of CABG. We assessed major adverse cardiac events, including cardiac death, myocardial infarction, ischemia-driven target-vessel revascularization, or reocclusion 1 year after successful CTO PCI in patients treated before February 2015. Post-CABG patients (175 cases) had a higher J-CTO score (2.5 versus 2.1; P=0.002). In-hospital complications were similar, although the incidence of contrast-induced nephropathy was higher in post-CABG patients (4.6% versus 1%; P=0.01). With multivariable analysis, post-CABG status was associated with higher incidence of 1-year major adverse cardiac event (hazards ratio=2.2; P=0.02). As a second level analysis, we looked at the feasibility and safety of CTO PCI via saphenous vein grafts (19% of post-CABG cases) versus collateral channels (36%) versus with an antegrade-only approach (45%), and assessed short-term outcomes and complications. High success was achieved in the saphenous vein graft group. In-hospital events were similar in the 3 groups. Post-CABG CTO PCI is associated with similar high success and low complications compared with CTO PCI in patients who never had CABG. However, it is associated with higher recurrent events at 1 year. To achieve high success rate, use of saphenous vein grafts as retrograde conduits seems to be safe and effective.

Survival after percutaneous coronary intervention for chronic total occlusion.

There is limited data on prognosis after percutaneous coronary intervention (PCI) for coronary chronic total occlusions (CTO) in the era of drug-eluting stents (DES). This study investigates the specific contribution of CTO recanalization to the survival benefit of complete revascularization. Consecutive patients who underwent PCI of a CTO at our center between 01/2005 and 12/2013 were followed for a median of 2.6years (interquartile range 1.1-3.1years). All-cause mortality was compared between patients with successful and failed PCI of CTO without and with adjustment for pertinent co-variables by the Cox models. The study comprised 2002 patients with attempted PCI of CTO (mean age 65.2±11years, 17% female), 82% had multivessel disease. The CTO PCI was successful in 1662 (83%) patients with a DES rate of 94%. All-cause mortality was significantly lower in patients with successful PCI of CTO compared to failed PCI of CTO (15.3 vs. 25.9% at 4years; P<0.001). In the multivariable model, both successful CTO PCI and complete revascularization were strong independent predictors of reduced long-term mortality (adjusted hazard ratio (HR) 0.72; 95% confidence interval (CI) 0.53-0.97; P=0.03 and adjusted HR 0.59; 95% CI 0.42-0.82; P=0.002). Also within the subset of incomplete revascularization, successful PCI of CTO was associated with reduced mortality (adjusted HR: 0.67; 95% CI: 0.50-0.92; P=0.012). Successful CTO recanalization is an independent predictor for improved long-term survival. Persistent CTO lesions are associated with significantly worse survival than persistent non-occlusive coronary lesions.

Theory and practical based approach to chronic total occlusions.

Coronary chronic total occlusions (CTOs) represent the most technically challenging lesion subset that interventional cardiologists face. CTOs are identified in up to one third of patients referred for coronary angiography and remain seriously undertreated with percutaneous techniques. The complexity of these procedures and the suboptimal success rates over a long period of time, along with the perception that CTOs are lesions with limited scope for recanalization, account for the underutilization of CTO Percutaneous Coronary Intervention (PCI). During the last years, dedicated groups of experts in Japan, Europe and United States fostered the development and standardization of modern CTO recanalization techniques, achieving success rates far beyond 90 %, while coping with lesions of increasing complexity. Numerous studies support the rationale of CTO revascularization following documentation of viability and ischemia in the territory distal to the CTO. Successful CTO PCI provide better tolerance in case of future acute coronary syndromes and can significantly improve angina and left ventricular function. Randomized trials are on the way to further explore the prognostic benefit of CTO revascularization. The following review reports on the theory and the most recent advances in the field of CTO recanalization, in an attempt to promote a more balanced approach in patients with chronically occluded coronary arteries.

The Application of Rotational Atherectomy in PCI of Coronary Chronic Total Occlusions

Objective:The aim of the study is to investigate the effi cacy, complication rate and predictors of rotational atherectomy (RA) usage after successful guidewire crossing during percutaneous coronary intervention (PCI) of coronary chronic total occlusion (CTO).Methods:A single center experience of 525 consecutive patients from October 2010 to June 2014. A total of 587 CTO lesions were treated. After successful guidewire crossing, lesions that could not be crossed with the smallest 1.25mm balloon underwent RA with 1.25mm and or 1.5mm burrs after exchanging for the Rotawire through a microcatheter. Post RA, the CTO lesions are then pre-dilated successfully before stenting with drug eluting stents (DES). Patients were then clinically followed up for inpatient MACE and restenosis.Results:587 CTO lesions in 525 patients were treated. The mean age of patients was 61.6 ± 10.2 years-old. 30% had diabetes mellitus. Mean LVEF was 56 ± 12%. The overall successful CTO PCI rate was 87%. 22% required the retrograde CTO approach. 26 CTO lesions in 26 patients (4.43%) underwent RA. RA and stent deployment were successfully performed in 25 patients. One lesion was unsuccessful because the Rotawire could not cross the lesion. Reference lesion diameter was 2.87±0.55mm,18 cases used the 1.25mm burr and 7 cases used the 1.5mm burr. Reference burr / vessel diameter ratio was 0.46± 0.20mm. No patients required adjunct 2b3a inhibitor usage. The procedural success rate was 96.2% and no peri-procedural MACE was observed.Conclusion:RA was a safe and effective adjunct therapy for calcifi ed CTO lesions that failed balloon dilatation.

Avoid overtreatment in the setting of chronic total occlusions: The role of blood flow restoration in positive vascular remodeling

A coronary chronic total occlusion (CTO) promotes negative remodeling in distal segments by negative vascular wall remodeling and plaque growth [ [1] Park J.J. Chae I.H. Cho Y.S. et al. The recanalization of chronic total occlusion leads to lumen area increase in distal reference segments in selected patients: an intravascular ultrasound study. JACC Cardiovasc. Interv. Aug 2012; 5: 827-836 Crossref PubMed Scopus (31) Google Scholar ]. As a result, epicardial coronary segments located distal to a CTO appear often as diffusely diseased arteries [ [2] Werner G.S. Schwarz G. Prochnau D. et al. Paclitaxel-eluting stents for the treatment of chronic total coronary occlusions: a strategy of extensive lesion coverage with drug-eluting stents. Catheter. Cardiovasc. Interv. 2006; 67: 1-9 Crossref PubMed Scopus (46) Google Scholar ]. It is unknown if these lesions are related to clinical events at follow-up and if they require percutaneous coronary intervention (PCI) with stenting, because blood flow restoration by recanalisation potentially leads to positive vascular remodeling in the distal reference segments [ [3] Gasparini G.L. Rossi M.L. Presbitero P. Follow-up improvement of distal vessel diameter after successful chronic total coronary occlusion recanalization. JACC Cardiovasc. Interv. Apr 2014; 7: e31-e33 Crossref PubMed Scopus (4) Google Scholar ]. Few data have been published to investigate the role of blood flow restoration in remodeling process after successful CTO PCI. A study of Park et al. [ [1] Park J.J. Chae I.H. Cho Y.S. et al. The recanalization of chronic total occlusion leads to lumen area increase in distal reference segments in selected patients: an intravascular ultrasound study. JACC Cardiovasc. Interv. Aug 2012; 5: 827-836 Crossref PubMed Scopus (31) Google Scholar ] showed that recanalization of a CTO led to lumen area increase in two-thirds of the patients. Independent predictors of lumen area increase were occlusion duration, a poor collateral flow and statin use. The degree of collateral flow might reflect the magnitude of hemodynamic stimuli deprivation, whereas the CTO duration correlates with the time in which vessels undergo a negative remodeling process. In a study of Galassi et al. [ [4] Galassi A.R. Tomasello S.D. Crea F. et al. Transient impairment of vasomotion function after successful chronic total occlusion recanalization. J. Am. Coll. Cardiol. Feb 21 2012; 59: 711-718 Crossref PubMed Scopus (70) Google Scholar ] authors have suggested that improvement of distal vessel diameter after CTO recanalization can be explained by an impaired endothelium-dependent and/or -independent vasomotion immediately after CTO recanalization, that improves at follow-up, or by a positive remodeling or by a combination of both. Gomez-Lara et al. [ [5] Gomez-Lara J. Teruel L. Homs S. et al. Lumen enlargement of the coronary segments located distal to chronic total occlusions successfully treated with drug-eluting stents at follow-up. EuroIntervention. Feb 2014; 9: 1181-1188 Crossref PubMed Scopus (32) Google Scholar ] have documented a notable late lumen enlargement between baseline and follow-up. These findings can be explained either by the absence of vasomotor response to non-endothelium-mediated stimuli immediately after the procedure and plaque regression. At follow-up, endothelium-independent response was restored in most patients, showing a remarkable luminal gain compared to the index procedure.

Percutaneous Treatment of Coronary Chronic Total Occlusions Part 1: Rationale and Outcomes.

Coronary chronic total occlusions (CTOs) are commonly encountered in patients with coronary artery disease. Compared to patients without coronary CTOs, those with CTO have worse clinical outcomes and lower likelihood of complete coronary revascularisation. Successful CTO percutaneous coronary intervention (PCI) can significantly improve angina and improve left ventricular function. Although currently unproven, successful CTO PCI might also reduce the risk for arrhythmic events in patients with ischaemic cardiomyopathy, provide better tolerance of future acute coronary syndrome, and possibly improve survival. Evaluation by a heart team comprised of both interventional and non-interventional cardiologists and cardiac surgeons is important for determining the optimal revascularisation strategy in patients with coronary artery disease and CTOs. Ad hoc CTO PCI is generally not recommended, so as to allow sufficient time for (a) discussion with the patient about the indications, goals, risks, and alternatives to PCI; (b) careful procedural planning; and (c) contrast and radiation exposure minimisation. Use of drug-eluting stents is recommended for CTO PCI, given the lower rates of angiographic restenosis compared to bare metal stents.