Chronic total occlusion: To treat or not to treat

Table 1 Chronic total occlusion prevalence, location and treatment applied in different studies n (%)

Ref.	Type of study	Population	CTO prevalence	CTO location			Medical treatment	PCI	CABG
				RCA	LAD	LCA
Kahn et al[2], 1993	Retrospective	333 Coronary disease (stenoses ≥ 50%)	101 (35)	58%	18%	24%	-	-	-
Christofferson et al[3], 2005	Retrospective	6581 Underwent coronarography because of suspected CD	1612 (25)	49.4%	22%	28.60%	49%	11%	40%
		3087 Coronary disease (stenoses ≥ 70%)	1612 (52)
Srinivas et al[4], 2002	Retrospective	1761 Multivessel disease	545 (31)	-	-	-	-	14.50%	-
Yamamoto et al[5], 2013	Prospective	15263 First revascularization procedure	2491 (19)	44.9%	41.10%	28.50%	-	61.18%	-
Fefer et al[6], 2012	Prospective	14439 Underwent coronariography because of suspected CD	2630 (18.2)	46.9%	19.86%	15.43%	64%	10%	26%
Jeroudi et al[7], 2013	Prospective	1015 Coronary disease (stenoses ≥ 50%)	319 (31.34)	-	-	-	19% (61)	50% (161)	30% (97)

CTO: Chronic total occlusion; RCA: Right coronary artery; LAD: Left anterior descending; LCA: Left circumflex artery; PCI: Percutaneous coronary intervention; CABG: Coronary artery bypass graft.

Table 2 Specific recommendations on the treatment of chronic total occlusion in the American and European Practice Guidelines

Society	Guideline	Specific recommendation on the treatment of CTO
EUROPEAN	2010 Guidelines of myocardial revascularization[9]	“Revascularization of CTO may be considered in the presence of angina or ischemia related to the corresponding territory”
	2013 ESC guidelines on the management of stable coronary artery disease[1]	“Revascularization needs to be discussed in patients with symptoms of occlusion or large ischemic areas”
AMERICAN	2011 ACCF/AHA Guideline for Coronary Artery Bypass Graft Surgery[10]	Not mentioned
	2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention[11]	Recommendation IIa. Evidence level B. PCI of a CTO in patients with appropriate clinical indications and suitable anatomy is reasonable when performed by operators with appropriate expertise “The decision to try PCI for a CTO (vs continued medical therapy or surgical revascularization) requires an individualized risk-benefit analysis encompassing clinical, angiographic, and technical considerations”
	2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease[12]	Not mentioned

CTO: Chronic total occlusion; ACCF: American College of Cardiology Foundation; AHA: American Heart Association; SCAI: Society for Cardiovascular Angiography and Interventions; ACP: American College of Physicians; AATS: American Association for Thoracic Surgery; PCNA: Preventive Cardiovascular Nurses Association; STS: Society of Thoracic Surgeons; PCI: Percutaneous Coronary Intervention.

Table 3 Specific recommendations on the treatment of chronic total occlusion in the 2012 ACCF/SCAI/STS/AATS/ASNC/HFSA/SCCT Appropriate Use Criteria for Coronary Revascularization Focused Update[14]

		ANGINA
		Asymptomatic	I	II	III	IV
Risk in the ischemia test	High	Uncertain	Appropriate	Appropriate	Appropriate	Appropriate	Max	Treatment level
		Uncertain	Uncertain	Uncertain	Appropriate	Appropriate	Med
		Uncertain	Uncertain	Uncertain	Appropriate	Appropriate	Min
	Medium	Uncertain	Uncertain	Uncertain	Appropriate	Appropriate	Max
		Inappropriate	Uncertain	Uncertain	Uncertain	Uncertain	Med
		Inappropriate	Uncertain	Uncertain	Uncertain	Uncertain	Min
	Low	Inappropriate	Inappropriate	Inappropriate	Uncertain	Uncertain	Max
		Inappropriate	Inappropriate	Inappropriate	Inappropriate	Inappropriate	Med
		Inappropriate	Inappropriate	Inappropriate	Inappropriate	Inappropriate	Min

It shows the 45 possible scenarios depending on the risk of mortality based on the findings on ischemia tests, symptoms and level of treatment.

Table 4 Findings on left ventricular ejection fraction and regional wall motion variations after percutaneous coronary intervention treatment of chronic total occlusion

	Type of study	Population	LVEF estimation	Follow up	Results
					LVEF	Regional wall motion	Symptoms	Collateral function	Ventricular remodeling
1994-1995 Sirnes et al[30]	Prospective	95 CTOs treated with PCI	Ventriculography	Angiography 6 mo	LVEF increase (from 0.62 ± 0.13 to 0.67 ± 0.12) P < 0.001	Increase in regional radial shortening (from 0.279 ± 0.106 to 0.319 ± 0.107) P < 0.001	Improvement in angina class	Not mentioned	Not mentioned
1999-2003 Werner et al[31]	Prospective	126 CTOs treated with PCI	Ventriculography	Angiography	LVEF increase (from 0.60 ± 0.19 to 0.67 ± 0.16) P < 0.001	Increase in wall motion severity index (from -1.92 ± 1.32 to -1.30 ± 1.28) P < 0.001	Not mentioned	No changes in collateral function	Not mentioned
2008 Kirschbaum et al[32]	Prospective	21 CTOs treated with PCI	NMR	NMR 5 mo and 3 yr	LVEF increase (from 60% ± 9% to 63% ± 11%) P = 0.11	Increase in segmental wall thickening. From 19% ± 21% to 31% ± 30% at 5 mo (P < 0.001) and 47% ± 46% at 3 yr (P = 0.04)	Not mentioned	Not mentioned	Less ventricular remodeling in NMR at 3 yr

LVEF: Left ventricular ejection fraction; CTO: Chronic total occlusion; PCI: Percutaneous coronary intervention; NMR: Nuclear magnetic resonance.

Table 5 Baseline characteristics of clinical and angiographic variables in studies included on Joyal meta-analisis[42]

Ref.	Age (yr)		Male sex (%)		Multivessel disease(%)		Diabetes (%)		LVEF (%)		NYHA class 3-4 (%)		Renal dysfunction(%)		Occlusion length (mm)		Calcified vessel (%)		Ischemic burden
	Success	Failure	Success	Failure	Success	Failure	Success	Failure	Success	Failure	Success	Failure	Success	Failure	Success	Failure	Success	Failure	Success	Failure
Finci et al[42], 1990	55 ± 11	55 ± 12	93	88	24	23	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d
Warren et al[43], 1990	54	55	53	47	48	52	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d
Ivanhoe et al[44], 1992	55 ± 10	56 ± 11	81	82	30	54 (0.0001)	10	15	55 ± 10	56 ± 11	3	3	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d
Angioï[45], 2000	55 ± 10	56 ± 11	52	88	37	45	10	11	59 ± 14	59 ± 14	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d
Noguchi et al[46], 2000	61 ± 9	61 ± 11	78	80	47	67 (0.01)	26	32	56 ± 12	54 ± 9	n/d	n/d	n/d	n/d	11.3 ± 8.3	14.1 ± 8.1 (< 0.05)	37	56 (< 0.01)	n/d	n/d
Suero et al[47], 2001	60 ± 11	61 ± 12	78	80	73	82 (0.001)	21	20	51 ± 14	52 ± 14	n/d	n/d	8.2	7.1	n/d	n/d	n/d	n/d	n/d	n/d
Olivari et al[48], 2003	58 ± 10	59 ± 11	86	85	45	60 (0.014)	17	20	56 ± 10	56 ± 10	9	7	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d
Hoye et al[49], 2005	60 ± 11	61 ± 10	74	72	54	67(0.03)	12	9.1	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d
Drozd et al[50], 2006	57 ± 10	58 ± 10	81	80	46	53	11	11	n/d	n/d	14.4	18 (NYHA ≥ 2)	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d
Aziz et al[51], 2007	59	59	76	81	50	40 (0.006)	14	9	53	53	12.2	15.7	0.3	1.8	n/d	n/d	n/d	n/d	n/d	n/d
Prasad et al[52], 2007	63 ± 11	64 ± 11	76	75	70	74	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d	n/d
Valenti et al[53], 2008	67 ± 11	70 ± 11	81	83	85	87	24	21	42 ± 13	41 ± 14	n/d	n/d	n/d	n/d	25 (15-52.5)	28 (21-47.5)	n/d	n/d	n/d	n/d
de Labriolle et al[54], 2008	61 ± 12	64 ± 10	72	87	45	66 (0.002)	19	40.5 (0.005)	50 ± 12	48 ± 15	n/d	n/d	9.1	6.3	n/d	n/d	n/d	n/d	n/d	n/d

LVEF: Left ventricular ejection fraction; n/d: No data; NYHA: New York Heart Association.