Improvement of left ventricular contraction and relaxation synchronism after recanalization of chronic total coronary occlusion by angioplasty

Circulating Chromogranin B Is Associated With Left Ventricular Functional Recovery After Successful Recanalization of Chronic Total Occlusion

Background: Chromogranin B (CgB) is increased in heart failure and proportionate to disease severity. We investigated whether circulating CgB level is associated with left ventricular (LV) functional recovery potential after successful recanalization of chronic total occlusion (CTO). Methods: Serum levels of CgB were assayed in 53 patients with stable angina with LV functional recovery [an absolute increase in LV ejection fraction (EF) of ≥5%] and 53 age- and sex-matched non-recovery controls after successful recanalization of CTO during 12-month follow-up. Results: We found that CgB level was significantly lower in the recovery group than in the non-recovery group (593 [IQR 454-934] vs. 1,108 [IQR 696-2020] pg/ml, P < 0.001), and that it was inversely correlated with changes in LVEF (Spearman's r = -0.31, P = 0.001). Receiver operating characteristic (ROC) analysis showed that the area under the curve of CgB for predicting LVEF improvement was 0.76 (95% CI 0.664-0.856), and that the optimal cutoff value was 972.5 pg/ml. In multivariate analyses, after adjusting for confounding factors, high CgB level remained an independent determinant of impaired LV functional recovery after CTO recanalization. LV functional improvement appeared to be more responsive to CgB in patients with poor than with good coronary collaterals. Conclusions: Elevated circulating CgB level confers an increased risk of impaired LV functional recovery after successful recanalization of CTO in patients with stable coronary artery disease.

Procedural and follow-up clinical outcomes after chronic total occlusion revascularization: Data from an Indian public hospital

BACKGROUND

Chronic total occlusion (CTO) continues to be challenging lesion subset for percutaneous intervention. Last decade has seen tremendous increase in percutaneous coronary intervention (PCI) in this subset owing to improved understanding of the anatomy and enhanced skillset with availability of dedicated hardware. We sought to study the outcomes of CTO PCI in an Indian public hospital.

METHODS

This was a single-center non-randomized descriptive follow-up study on CTO PCI. The end-points were procedural success, immediate, and late adverse cardiovascular events [major adverse cardiac event (MACE)] and change in angina and left ventricular function at follow-up.

RESULTS

A total 389 CTO lesions were treated with a success rate of 87% (339/389). The mean Japanese chronic total occlusion (J-CTO) score was 1.78 ± 0.12 (mean ± standard deviation). Multivariate analysis of different angiographic components of J-CTO score identified tortuosity (p = 0.001), calcifications (p ≤ 0.001), and blunt stump (p = 0.007) as independent predictors of procedural failure. The periprocedural mortality was less than 1%, and the non-life threatening complications were about 4%. The MACE rate was significantly higher in the procedural failure group (60%) than in the procedural success group (5.3%, p < 0.001). An increase in left ventricular ejection fraction (LVEF) was noted following successful CTO PCI after complete revascularization.

CONCLUSIONS

The success rates for CTO PCI in this registry were about 87%. Immediate and long-term clinical outcomes were better with lower MACE (5%) after a successful procedure. A key outcome variable included an increase in LVEF among patients after a successful CTO PCI. The overall periprocedural complications were about 5.5%, but majority were non-life threatening.

Evaluation of left ventricular function after percutaneous recanalization of chronic coronary occlusions : The role of two-dimensional speckle tracking echocardiography

Background

This study evaluated the feasibility of using two-dimensional speckle tracking echocardiography (2D-STE) to monitor left ventricular (LV) and overall function after percutaneous recanalization.

Methods

LV function after percutaneous recanalization was monitored by 2D-STE and conventional echocardiography in 43 patients with coronary chronic total occlusion (CTO) who underwent primary percutaneous coronary intervention (PCI). Follow-ups were carried out 1 day as well as 3 and 6 months after CTO-PCI. At each time point, LV ejection fraction (LVEF) was examined by echocardiography, and LV global longitudinal strain (GLS) was measured by 2D-STE.

Results

It was found that the global longitudinal strain assessed with 2D-STE was improved as early as 1 day after CTO-PCI, whereas LVEF tended to improve up to 3 and 6 months after CTO-PCI.

Conclusion

PCI can effectively improve LV function in patients with CTO. 2D-STE is a superior technique for objectively quantifying the functional change earlier.

Comparison of Benefit of Successful Percutaneous Coronary Intervention for Chronic Total Occlusion in Patients With Versus Without Reduced (≤40%) Left Ventricular Ejection Fraction

Successful recanalization of chronic total occlusions (CTO) has been associated with improved survival. Data on outcomes in patients with left ventricular (LV) systolic dysfunction undergoing percutaneous coronary intervention for CTO, however, are scarce. Between January 2005 and December 2013, a total of 2,002 consecutive patients undergoing elective CTO percutaneous coronary intervention at a tertiary care center were divided into patients with (LV ejection fraction ≤ 40%) and without (LV ejection fraction > 40%) LV systolic dysfunction as defined by transthoracic echocardiography. The primary end point was all-cause mortality. Median follow-up was 2.6 (1.1 to 3.1) years. A total of 348 (17.4%) patients had LV dysfunction. All-cause mortality was higher in patients with LV dysfunction (30.2%) than in those with normal LV function (8.2%, p <0.001), and associations remained significant after adjustment for baseline differences (adjusted hazard ratio [HR] 3.39, 95% confidence interval [CI] 2.57 to 4.47, p <0.001). Successful CTO recanalization was independently associated with reduced all-cause mortality, with similar relative risk reductions in both the preserved (6.6% vs 16.9%, adjusted HR 0.48, 95% CI 0.34 to 0.70, p <0.001) and the reduced LV function groups (26.2% vs 45.2%, adjusted HR 0.63, 95% CI 0.41 to 0.98, p = 0.04, interaction p = 0.28). In conclusion, irrespective of LV function, successful CTO recanalization is associated with a clear survival benefit.

Determinants of Left Ventricular Systolic Function Improvement Following Coronary Artery Revascularization in Heart Failure Patients With Reduced Ejection Fraction (HFrEF)

Revascularization therapy such as percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) should be considered for heart failure with reduced ejection fraction (HFrEF). However, revascularization therapy does not always improve left ventricular ejection fraction (LVEF). The purpose of this study was to investigate the determinants of LVEF improvement following revascularization in HFrEF patients. From 2,229 consecutive decompensated heart failure patients, a total of 47 HFrEF patients who underwent revascularization were included in the analysis. Improvement of LVEF was defined as [(LVEF during chronic phase) - (LVEF during acute phase)] ≥ 10%. Univariate and multivariate logistic regression analyses were applied to investigate the determinants of LVEF improvement. The prevalence of revascularization by PCIs including chronic total occlusion (CTO) was significantly greater in the improved EF group (45.0%) as compared to the non-improved EF group (11.1%) (P = 0.02). Multivariate logistic regression analysis revealed that revascularization by PCIs including CTO was the significant determinant of the LVEF improvement after adjusting for confounding factors (OR 5.43, 95% CI 1.06-27.74, P = 0.04). Optimal medical therapy (angiotensin-converting enzyme (ACE) inhibitor and/or angiotensin II receptor blocker (ARB) and beta-blockers) was less frequently prescribed in patients with CABG (50.0% for ACE inhibitor and/or ARB and 41.7% for beta-blocker) than in patients without CABG (94.3% for both) (P < 0.01 and P < 0.001, respectively). In conclusion, revascularization by PCIs including CTO was the significant determinant of LVEF improvement in HFrEF patients. Our results underscore the importance of optimal medical therapy even if patients receive complete revascularization such as CABG.

Update on Coronary Chronic Total Occlusion Percutaneous Coronary Intervention

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has significantly evolved during recent years. High success rates are being achieved by experienced centers and operators, but not at less-experienced centers. Use of CTO crossing algorithms can help improve the success and efficiency of these potentially lengthy procedures. There is a paucity of clinical trial data examining clinical outcomes of CTO PCI, which is critical for further adoption and refinement of the procedure. We provide a detailed overview of the clinical evidence and current available crossing strategies, with emphasis on recent developments and techniques.

Analysis of Plaque Composition in Coronary Chronic Total Occlusion Lesion Using Virtual Histology-Intravascular Ultrasound

Background and Objectives

Success rates of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) have recently been reported to range from 80% to 90%. A better understanding of the pathologic characteristics of the CTO lesion may helpful to improving CTO PCI success rates. We evaluated the CTO lesion in patients with stable angina (SA) by virtual histology-intravascular ultrasound (VH-IVUS).

Subjects and Methods

The study population consisted of 149 consecutive patients with SA underwent VH-IVUS examination. We analyzed demographic and VH-IVUS findings in 22 CTO patients (17 males; mean, 62.3 years old) compared with 127 non-CTO patients (82 males; mean, 61.3 years old).

Results

A significantly lower ejection fraction (57.6±13.0% vs. 65.4±8.8%, p=0.007) was detected in the CTO group compared with the non-CTO group. Reference vessel lumen area of the proximal and distal segment was significantly less in CTO group than in non-CTO group. The lesion length of the CTO group was significantly longer than those of the non-CTO group (24.4±9.6 mm vs. 17.2±7.4 mm, p<0.001). Total atheroma volume (224±159 mm³ vs. 143±86 mm³, p=0.006) and percent atheroma volume (63.2±9.6% vs. 55.8±8.5%, p=0.011) of the CTO group were also significantly greater than those of non-CTO group. However, the lesion length adjusted plaque composition of the CTO group was not significantly different compared with that of the non-CTO group.

Conclusion

CTO lesions had a longer lesion length and greater plaque burden than the non-CTO lesion in patients with SA. However, lesion length adjusted plaque composition showed similar between the two groups. These results support that plaque characteristics of CTO lesions are similar to non-CTO lesions in patients with SA.

Evidence for Benefit of Percutaneous Coronary Intervention for Chronically Occluded Coronary Arteries (CTO) - Clinical and Health Economic Outcomes

Percutaneous revascularisation of a coronary chronic total occlusion (CTO) remains one of the technical frontiers of interventional cardiology. CTOs are common, and yet intervention is only attempted in 10 % of cases. CTO procedures are perceived to be technically challenging, lengthy, associated with significant risk and have only limited data to support the practise. Recent technical advances have dramatically increased the success rate, shortened procedural time and improved clinical outcomes. The aim of this article is to critically examine the data that supports CTO intervention, including specifically an appraisal of procedural safety, benefit and overall cost effectiveness.

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.

Advances in the management of coronary chronic total occlusions

Chronic total occlusions (CTOs) have been called "the last frontier" of percutaneous coronary intervention (PCI) due to traditionally low success rates and high risk for restenosis and re-occlusion. Recent advances in equipment and crossing techniques have significantly increased CTO PCI success rates while maintaining low risk of complications. Specifically, the retrograde approach and controlled antegrade dissection and re-entry in conjunction with advanced guidewires and microcatheters have significantly improved procedural success rates. Moreover, the introduction of the "hybrid" approach has created a unified framework for operators to approach CTOs in a systematic and efficient fashion. Finally, drug-eluting stents, especially second generation, have improved long-term patency after CTO PCI.

Thrombotic Occlusion during Intravascular Ultrasonography-Guided Percutaneous Coronary Intervention of Stumpless Chronic Total Occlusion

Percutaneous coronary intervention (PCI) of stumpless chronic total occlusion (CTO) lesions with a side branch stemming from the occlusion have a significantly lower treatment success rate because physicians cannot identify an accurate entry point with only conventional angiographic images. An intravascular ultrasonography (IVUS)-guided wiring technique might be useful for the penetration of stumpless CTO. We recently experienced thrombotic occlusion during an IVUS-guided stumpless CTO procedure. The cause of the thrombosis is not completely understood; the thrombosis may have been associated with the long use of the IVUS catheter. Special precautions should be taken to prevent thrombus in such cases.

Early assessment of percutaneous coronary interventions for chronic total occlusions analyzed by novel echocardiographic techniques

OBJECTIVE

Successful revascularization of chronic total occlusions has been associated with improved left ventricular systolic function, reduced anginal symptoms, increased exercise capacity, and increased survival. This study was conducted to determine the impact of revascularization in chronic total occlusion on left ventricular function using novel echocardiographic techniques.

METHODS

A total of 129 patients with chronic total occlusion who underwent revascularization between April 2011 and November 2012 were included in this study. Echocardiographic assessments with two-dimensional speckle tracking echocardiography and real-time three-dimensional echocardiography were performed before the procedure and one month after the procedure. The left ventricular ejection fraction, left ventricular volumes, and three-dimensional systolic dyssynchrony index were quantified.

RESULTS

An immediate procedural success was obtained in 118 patients (91.5%). There were no acute or subacute stent thromboses during follow-up. The mean left ventricular ejection fraction significantly increased (p<0.001), while the left ventricular end-diastolic and end-systolic volumes significantly decreased (p = 0.001 and p<0.001, respectively). The three-dimensional systolic dyssynchrony index also decreased significantly (p<0.001). The global longitudinal strain showed a significant increase after successful revascularization (p<0.001). An increase in the global longitudinal strain was correlated with an increase in the left ventricular ejection fraction (r = 0.27, p = 0.02). The patients with a left ventricular ejection fraction ≥50% displayed a greater improvement in the global longitudinal strain, and the patients with diabetes showed less improvement.

CONCLUSIONS

Using novel echocardiographic techniques, our results showed that restoring the coronary blood flow in chronic total occlusion patients reduces the left ventricular volumes and improves the left ventricular ejection fraction and the global longitudinal strain of hibernating myocardium.

Rescue percutaneous coronary recanalization of right coronary artery by retrograde approach

We describe the case of a 62-year-old female patient in whom there was an occlusion of collaterals and acute inferior wall ischemia during the opening procedure of right coronary artery (RCA) chronic total occlusion. Rescue percutaneous coronary intervention (PCI) of RCA by the retrograde approach was performed preventing heart muscle damage. In this article we discuss the issue of PCI by the retrograde technique.

Radial approach and single wiring as first intentional strategies in chronic total occlusions of the left anterior descending coronary artery

BACKGROUND

Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) of the left anterior descending coronary artery (LAD) specifically is associated with improved long-term 5 years survival as compared to PCI failure. Simpler PCI techniques may be successful and safer than complex techniques which are perceived to have high failure rates and technical complexity. We aimed to describe the safety and effectiveness of first intentional single wiring and radial approach in the treatment of patients with a CTO of the native LAD coronary artery at Toulouse Rangueil university hospitals.

PATIENTS AND METHODS

The study was a single center prospective registry. All patients showed evidence of myocardial viability in LAD territory. The operators' initial strategy was to start by a radial access as a first choice whenever feasible; if not, a femoral access was chosen. The initial strategy for lesion crossing in either antegrade or retrograde approaches was single wiring by lesion crossing using one guidewire (GW) as a simple technique.

RESULTS

A total of 30 patients with 30 LAD CTO lesions (100%) were recorded. Mean age was 71.6 + 15 years, 77% were males and 23% were females. The access route was radial 66% of the time and femoral 54% of the time and with double access for contralateral injection in 40% of the patients. Sheaths and catheters sizes 6F were used in 53% of the patients, and 7F in 73% of the patients. Overall lesion success rate was 83% of lesions. Single wiring was the prevailing technique used in 97% of successful lesions (83% of total cases), while only 3% were by multiple wiring techniques. Successful single antegrade wiring represented 63% of our total study cases with a GW success rate of 92% of cases. Successful single retrograde wiring represented 13% of our cases with a GW success rate of 67%. Q-wave myocardial infarction (MI), stent thrombosis, stroke, emergency coronary artery bypass graft (CABG), major bleeding, radiation dermatitis, cardiac tamponade or clinical perforation requiring any hemostatic maneuvers did not occur. There was a post-procedural Troponin rise of 3x normal levels in 30% of patients, and contrast induced nephropathy in 7%. Intra-aortic balloon counterpulsation (IABCP) was used in 3% of patients and cardiac death occurred in 3% of patients.

CONCLUSION

Single wiring and radial access as initial strategies in PCI for LAD-CTO lesions in either approaches antegrade or retrograde are associated with a high procedural success rate and an acceptable incidences of adverse events.

Comparison of five-year outcome of sirolimus-eluting stent implantation for chronic total occlusions versus for non-chronic total occlusion (from the j-Cypher registry)

The aim of this study was to evaluate the 5-year clinical outcomes of patients who underwent sirolimus-eluting stent implantation for chronic total occlusion (CTO). Among 10,759 patients treated exclusively with sirolimus-eluting stent in the j-Cypher registry, clinical outcomes were compared between 1,210 patients with revascularization for CTO and 9,549 patients with revascularization for non-CTO only. The cumulative 5-year incidence of all-cause death (13.2% vs 14.3%, p = 0.56) and definite stent thrombosis (1.9% vs 1.6%, p = 0.76) was similar between the 2 groups. The adjusted risk for CTO relative to non-CTO for all-cause death and definite stent thrombosis was insignificant (hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.81 to 1.16, and HR 0.99, 95% CI 0.6 to 1.65, respectively). The cumulative incidence of target lesion revascularization was significantly higher in the CTO group (20.7% vs 14.8%, p <0.001). The adjusted risk for target lesion revascularization was significant (HR 1.31, 95% CI 1.13 to 1.52, p <0.001). In the subgroup analysis, the risk for CTO for all-cause death tended to be lower in the subgroup of patients with left ventricular ejection fractions ≤40% (HR 0.68, 95% CI 0.45 to 1.01, p = 0.053), while the risk was significantly higher in the subgroup of patients with end-stage renal disease without hemodialysis (HR 1.66, 95% CI 1.02 to 2.70, p = 0.04). In conclusion, sirolimus-eluting stent implantation for CTO appears to be as safe as that for non-CTO for up to 5 years, except for the modestly elevated risk for target lesion revascularization and the higher risk for all-cause death in patients with end-stage renal disease without hemodialysis.

A novel modification of the retrograde approach for the recanalization of chronic total occlusion of the coronary arteries intravascular ultrasound-guided reverse controlled antegrade and retrograde tracking

OBJECTIVES

The study evaluates the feasibility and efficacy of the novel modification of the retrograde recanalization of the chronic total occlusion (CTO) of the coronary arteries by using intravascular ultrasound (IVUS)-guided reverse controlled antegrade and retrograde tracking (CART).

BACKGROUND

Despite improvement in the techniques and materials, CTO recanalization is still suboptimal. The CART procedure has improved success rates, but there are certain inherent technical uncertainties and risk with this procedure.

METHODS

This first series involves 31 patients, with 22 patients having previous failed attempts at CTO recanalization. All patients were treated with bilateral approach and using IVUS-guided reverse CART concept.

RESULTS

Successful recanalization of the CTO was achieved in all cases (100%). The access route was septal collateral in 20 (70%) cases and epicardial collateral in 11 (30%) cases. IVUS guidance was used successfully in 30 cases, and the channel dilator (microcatheter) was used in 27 cases. Guidewire injury and grade 1 perforation was seen in 3 (9%) cases, which were managed conservatively. There was no death, coronary artery bypass surgery, or pericardiocentesis in this group of patients. Mean fluoroscopy time was 65.84 +/- 23.16 min, ranging from 31 to 106 min and total contrast volume used 321.32 +/- 137.77 ml (range 115 to 650 ml).

CONCLUSIONS

This first series describes a high success rate of CTO recanalization with IVUS-guided reverse CART in selected patients performed by an experienced operator.

Contemporary success and complication rates of percutaneous coronary intervention for chronic total coronary occlusions: results from the ALKK quality control registry of 2006

AIMS

Despite successful prevention of lesion recurrence by drug-eluting stents (DES), and the advancement in procedural techniques in the treatment of chronic total coronary occlusions (CTO), the number of CTOs treated by percutaneous coronary intervention (PCI) is still low as compared to their prevalence. This study aims to assess the outcome of PCI for CTOs in a contemporary survey of PCI in interventional centres in Germany.

METHODS AND RESULTS

The basis of this analysis is the 2006 quality assessment database of PCI conducted by the ALKK (working group of cardiology centres). Thirty-five centres contributed to this database, representing about 10% of all interventional centres of Germany. From a total of 20,502 patients, 8,882 patients with stable angina were selected. Of these 674 patients (7.6%) underwent PCI for a CTO. Their procedural characteristics and the hospital outcome were compared with patients treated for non-occlusive lesions. As compared to non-occlusive lesions, less patients underwent ad hoc PCI for a CTO. The fluoroscopy time was almost double of that in non-occlusive lesions, and contrast usage was significantly higher. The success rate was 60.1% as compared to 97.3% (p<0.001). Severe intraprocedural and in-hospital complications were similar for CTO and non-CTO lesions. Almost all patients with a CTO received a stent; DES were used in 53.4%, which was higher than the rate in non-CTO lesions (38.9%; p<0.001).

CONCLUSIONS

Although the success rate for PCI in CTOs is still well below that in non-occlusive lesions, this procedure is safe, encouraging its wider application. The low rate of DES use did not reflect the evidence for DES in CTOs.

Antegrade, retrograde, and combination strategies for chronic total occlusions

Chronic total occlusion (CTO) represents one of the most challenging lesion subsets faced by the interventional cardiologist. CTO is a common problem, being present in more than 30% of patients undergoing coronary angiography. Over the past 10 years, the success rate of recanalization has increased from approximately 50-85%. Developments in guidewire technology, imaging technique, and coronary devices have contributed to the improved prognosis of patients affected by a CTO lesion. Enhancement in antegrade and retrograde techniques of recanalization also result in improved outcomes. Benefits of CTO recanalization may include symptom relief, decreased need for coronary artery bypass graft surgery, improved left ventricular ejection fraction, and in some cases an improved survival.

The efficacy of a bilateral approach for treating lesions with chronic total occlusions the CART (controlled antegrade and retrograde subintimal tracking) registry

OBJECTIVES

The aim of this study was to evaluate the safety and feasibility of a new concept for chronic total occlusion (CTO) recanalization-using a bilateral approach that utilizes a Controlled Antegrade and Retrograde subintimal Tracking (CART) technique.

BACKGROUND

Successful percutaneous recanalization of coronary CTOs results in improved long-term outcomes. The recanalization of CTOs in native coronary arteries no doubt represents one of the most technically challenging of interventional procedures.

METHODS

A total of 224 consecutive patients (mean age 61 +/- 9 years; 86.2% men) were enrolled in this prospective multicenter registry. This technique combines the simultaneous use of antegrade and retrograde approaches. A subintimal dissection is created in both antegrade and retrograde fashion, thereby limiting the extension of the subintimal dissection within the CTO portion.

RESULTS

Of 224 CTO lesions (>3 months in duration) undergoing attempted recanalization using the CART technique, 145 cases (64.7%) had undergone previous CTO recanalization attempts. The success rates of crossing in a retrograde fashion with a wire and a balloon were 87.9% and 79.9%, respectively. The overall technical and procedural success rates achieved in this registry were 92.4% and 90.6%, respectively.

CONCLUSIONS

A bilateral approach for CTO lesions using the CART technique is feasible, safe, and has a higher success rate than previous approaches. These results indicate that a bilateral technique can solve a major dilemma that commonly affects CTO procedures.

Chronic total coronary occlusions in patients with stable angina pectoris: impact on therapy and outcome in present day clinical practice

BACKGROUND

Chronic total coronary occlusions (CTOs) represent a subgroup of coronary lesions with a low procedural success and high recurrence rate. However, there is evidence for a prognostic benefit of revascularizing a CTO.

OBJECTIVE

This study assessed the prevalence of CTOs among patients with stable angina pectoris and its impact on therapeutic strategies.

METHODS

Between 2001 and 2003, a survey was conducted in 64 sites to analyze the outcome of the first diagnostic angiography in patients presenting with stable angina pectoris (STAR registry). The clinical characteristics, initial angiographic findings, therapeutic strategy and outcome within the first year were analyzed.

RESULTS

A total of 2,002 patients were entered into the registry. One-third had at least one CTO. At 1 year, the mortality in patients with a CTO was significantly higher than in those without a CTO (5.5 vs. 3.1%; P = 0.009). This excess mortality was related to a higher prevalence of confounding factors in patients with a CTO such as diabetes and more severe LV dysfunction. Patients with a CTO were more likely to undergo surgery or being treated medically, whereas patients without a CTO were more likely to undergo PCI. If a CTO was treated by PCI the periprocedural and long-term outcome was similar to those with PCI for a non-occlusive lesion. However, periprocedural MACE was higher for patients treated for a non-occlusive lesion without first treating the CTO.

CONCLUSIONS

The prevalence of CTOs in patients with stable angina pectoris is high, and it influences the clinical outcome within the first year. The therapeutic strategy is influenced towards a rather conservative approach and lower rates of interventional therapy.

[Why perform PCI of coronary chronic occlusion and how?]

Angioplasty of coronary chronic total occlusion (CTO), defined by complete occlusion of coronary vessel with TIMI 0 flow greater than 3 months, has been avoided for many years, single vessel diseases being medically treated and multivessel diseases sent to surgeons mainly because a low success and high restenosis rates. Major improvements in devices and techniques mainly coming from Japan created a new concern about when and how to perform PCI of CTO. Clearly CTO are stable lesions but during the last years it was demonstrated that while comparing success and failure of recanalization, success improved symptoms, ischemia, left ventricular function, and even survival. Reopening CTOs can also decrease the risk of death and cardiogenic shock associated with a future acute coronary event. Selection of cases for PCI is based on well-known predictors of failure (calcifications, tortuosities, length of occluded segment and age of occlusion), on operator's experience and on a proof of viability and ischemia of the myocardium depending from occluded vessel (MRI). Many specific devices (powerful wires, microcatheters and coaxial balloons, specific guiding catheters, Tornus) and techniques (anterogrades and retrogrades through trans-septal collateral vessels) have been developed to increase success rate (70 to 90% in high volume operator hands). Outside of coronary perforations which are no more frequent in CTO lesions, some specific problems are important limitations: X-Ray exposure, contrast medium volume, and cost. With the success rate these complications are good reasons to have these procedures (or the most complex) performed by specialists.

The revascular active percutaneous interventional device for coronary total occlusions study

BACKGROUND

Despite the well-documented benefit of recanalization of an occluded vessel in some symptomatic patients, attempt is only performed in a minority of them. Percutaneous coronary intervention (PCI) of CTO is associated with high incidence of complications and unsuccessful procedure, mainly due to inability to cross the lesion. We sought to evaluate the efficacy and safety of the novel RVT CTO Guidewire Device (RVT-GDW, ReVascular Therapeutics, Sunnyvale, CA) in this complex scenario.

METHODS

The RAPID-CTO study is a non-randomized, single center, first-in-man evaluation of a new guidewire system for treatment of CTO. The RVT-GDW is a new device designed to provide enhanced penetration and positioning control for crossing CTO via: (1) an 0.014 "guidewire with a mechanically active distal end; (2) a handle attached proximally to the guidewire, with an adjustable torquer, and interfaced to (3) a non-disposable, battery-operated, control unit, that provides activation control and audio feedback during the CTO crossing procedure. Per protocol, the RVT-GDW device was only used after at least 5 min (fluoroscopy time) of attempt with commercially available conventional guidewires to cross the target lesion.

RESULTS

A total of 16 patients (16 lesions) were treated with the RVT-GDW. Mean age was 56.25 years, 56.2% were men, and 25% diabetics. The average duration of occlusion was 4.7 +/- 2.1 months. The mean vessel reference diameter was 2.76 +/- 0.31 mm and the mean lesion length was 16.64 +/- 7.70 mm (range 4.37-35.0 mm). Thirteen patients (81.2%) had "tapered stump" morphology at the proximal end of the occlusion, and a side branch was involved in 12 (75.0%). All lesions had contralateral circulation; bridging collaterals were seen in three (18.7%). Procedural success was achieved in 10 lesions (62.5%), with an average procedural time of 111.43 +/- 35.76 min. There were no major adverse cardiac events at both in-hospital and 30-day clinical follow-up.

CONCLUSIONS

The first-in-man RAPID-CTO study suggests that the novel RVT-GDW device is technically feasible, safe and effective in crossing chronically occluded coronary arteries. Larger studies are warranted.

Cardiac magnetic resonance imaging at 3 and 15 months after application of circulating progenitor cells in recanalised chronic total occlusions

BACKGROUND

Transplantation of circulating progenitor cells (CPC) improves left ventricular function after successful recanalisation of chronic total occlusions at short-term follow-up. Cardiac magnetic resonance imaging (CMRI) is an excellent tool for serial assessment of underlying structural changes in perfusion, left ventricular function, and infarct size.

METHODS

Twenty-eight patients with reperfused chronic total occlusion were randomised to CPC or inactive serum (control) infused into the target vessel. Serial CMRI was performed at baseline, after 3 and 15 months.

RESULTS

Serial CMRI revealed an increase in ejection fraction in CPC (from 51+/-12% to 58+/-11% and 59+/-11%; p<0.01 versus baseline) and a decrease in endsystolic volume (from 74+/-30 ml to 65+/-30 ml and 63+/-31 ml; p<0.05 versus baseline). Infarct size decreased from 14.4+/-9.3% to 11.6+/-8.9% and 10.3+/-8.9% left ventricle (p<0.01 versus baseline). Myocardial perfusion revealed an improvement in affected segments from 1.50+/-0.17 to 1.76+/-0.16 and 1.82+/-0.20 (p<0.001). In control ejection fraction showed no increase at 3 (p=0.99) and a trend towards improvement at 15 months (p=0.07), whereas perfusion improved at 3 (p=0.01) and 15 months (p=0.004) follow-up.

CONCLUSIONS

Analysis of serial CMRI suggests that CPC application after chronic total occlusion recanalisation is associated with improved myocardial perfusion, reduction in infarct size and subsequent improved recovery of left ventricular function as compared to control at short- and long-term follow-up.

Evaluation of left ventricular function three years after percutaneous recanalization of chronic total coronary occlusions

We investigated early and late effects of percutaneous revascularization for chronic total coronary occlusion on left ventricular (LV) function and volumes. Magnetic resonance imaging was performed in 21 patients before and 5 months and 3 years after recanalization. Global LV function and volumes and segmental wall thickening (SWT) were quantified on cine images. The 2 viability indexes used were the transmural extent of infarction (TEI) on delayed contrast enhancement images and end-diastolic wall thickness at baseline. Significant decreases in mean end-diastolic (86 +/- 14 to 78 +/- 15 ml/m2; p = 0.02) and mean end-systolic volume indexes (35 +/- 13 to 30 +/- 13 ml/m2; p = 0.03) were observed 3 years after recanalization. Mean ejection fraction tended to improve (60 +/- 9% to 63 +/- 11%; p = 0.11). SWT significantly increased at 5-months' follow-up (p <0.001), and an additional improvement was found at 3 years' (p = 0.04) follow-up in segments with TEI <25%. In segments with TEI of 25% to 75%, SWT was unchanged at 5-month follow-up (p = 0.89), but improved at 3 years (p = 0.04). SWT was unchanged in segments with transmural scars. For segmental functional recovery, TEI was a better predictor than end-diastolic wall thickness at baseline (odds ratio 5.6, 95% confidence interval 1.5 to 21.1, p = 0.01 vs odds ratio 2.5, 95% confidence interval 0.7 to 8.3, p = 0.14). In conclusion, a positive effect on LV remodeling and ejection fraction was observed up to 3 years after recanalization. Both early and late improvements in regional LV function were observed in the perfusion territory of chronic total coronary occlusion and were related to the transmural extent of infarction on pretreatment magnetic resonance imaging.

Improvement of the primary success rate of recanalization of chronic total coronary occlusions with the Safe-Cross system after failed conventional wire attempts

BACKGROUND

In view of the improved long-term patency with drug-eluting stents, the challenge with chronic total coronary occlusion (CTO) remains the low primary success rate. Improved guide wires have increased this rate, but alternative devices may be of additional value. The goal of the present study was to determine the additional benefit of a new penetration device in CTOs after an extensive conventional wire approach.

METHODS AND RESULTS

In 148 consecutive patients the recanalization of a CTO of >3 months was attempted. A conventional wire approach was used with recent dedicated recanalization wires, which was successful in 104 patients (70%). If after at least 20 min of fluoroscopic time no crossing of the wire was achieved, the Safe-Cross wire (SC) (Intralumina) was used which enables verification of the intraluminal wire position via optical reflectometry, and crossing of resistent occlusion caps by radiofrequency ablation. Due to severe dissections after the conventional approach, the SC was not used in 10 patients. In 34 patients the SC wire was applied, leading to successful lesion crossing in 14 patients (41%). Thus, the primary success rate was improved from 70.2% to 79.7%. No periprocedural major adverse events were observed with the SC wire. The successful attempts with the SC wire were predominantly in blunt occlusions. All patients with successful wire passage could be treated with one or more stents.

CONCLUSIONS

In a real world cohort of patients with CTO, the SC wire could increase the primary success rate after failed extensive conventional wire attempt. In these worst case patients the SC success rate was 41%. This new wire appears to have additional potential in failures of a conventional wire approach.

Coronary septal collaterals as an access for the retrograde approach in the percutaneous treatment of coronary chronic total occlusions

OBJECTIVES

To investigate the feasibility and safety of the percutaneous dilatation of coronary septal collaterals and to allow its use as an access for retrograde approach to percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTOs).

BACKGROUND

Despite improvements in percutaneous techniques and materials, CTO recanalization success rate is still suboptimal. The retrograde approach allows to significantly increase this success rate. However, its application via a bypass graft or epicardial collateral can potentially result in severe complications. A safer retrograde access is desired and would allow broadening the application of the retrograde approach in the percutaneous treatment of CTOs.

METHODS

After a failed antegrade CTO recanalization attempt, a retrograde approach via septal collaterals was tried in 21 patients (19 males, 2 females). The septal collateral was accessed via the contralateral patent coronary artery and was crossed with a hydrophilic floppy wire. After successful wire crossing of the septal collateral, sequential low pressure dilatation was performed with a 1.25 or 1.5 mm balloon to allow the delivery of a balloon catheter up to the distal CTO site.

RESULTS

Successful wire crossing and balloon dilatation of septal collaterals was achieved in 19 cases and in 17 cases, respectively. Postdilatation septal collateral diameter increased significantly reaching a mean diameter of 1.46 +/- 0.38 mm. Retrograde CTO recanalization was successfully performed in 71% of the cases. No major complications occurred.

CONCLUSIONS

Coronary septal collaterals can be used as an access for the retrograde approach in the percutaneous treatment of CTOs.

Advanced wiring technique for chronic coronary total occlusions

Percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) is one of the greatest challenges in interventional cardiology. The procedural success rate is relatively low, mainly due to guidewire failure to cross the occlusion. An effective wiring technique is the key to the success of CTO-PCIs. However, success or failure of wire crossing is mostly dependent on an operator's experience and skill. To improve the success rate of CTO-PCI in current interventional cardiology, several techniques were introduced in the Japanese CTO club. In this article, some advanced wiring techniques developed by the Japanese CTO club will be explored.

Prediction of Left Ventricular Function After Drug-Eluting Stent Implantation for Chronic Total Coronary Occlusions

OBJECTIVES

We studied the effect of drug-eluting stent implantation for chronic total coronary occlusion (CTO) on left ventricular volumes and function and assessed the predictive value of magnetic resonance imaging (MRI) performed before revascularization.

BACKGROUND

The effect of recanalization of CTO on long-term left ventricular function and the value of myocardial viability assessment with MRI is incompletely understood.

METHODS

Twenty-seven patients underwent contrast-enhanced MRI before and five months after successful drug-eluting stent implantation for CTO. A CTO was defined as a complete occlusion of a major epicardial coronary artery existing for at least six weeks (mean, 7 +/- 5 months). Myocardial wall thickening and left ventricular volumes were quantified on cine-images, and the transmural extent of infarction (TEI) was scored on delayed-enhancement images.

RESULTS

A significant decrease in mean end-systolic volume index (34 +/- 13 ml/m2 to 31 +/- 13 ml/m2; p = 0.02) and mean end-diastolic volume index (84 +/- 15 ml/m2 to 79 +/- 15 ml/m2; p < 0.002) was observed, whereas the mean ejection fraction did not change significantly (61 +/- 9% to 62 +/- 11%; p = 0.54). The extent of the left ventricle that was dysfunctional but viable before revascularization was related to improvement in end-systolic volume index (R = 0.46; p = 0.01) and ejection fraction (R = 0.49; p = 0.01) but not to the end-diastolic volume index (R = 0.10; p = 0.53). Segmental wall thickening improved significantly in segments with <25% TEI (21 +/- 15% to 35 +/- 25%; p < 0.001), tended to improve in segments with 25% to 75% TEI (18 +/- 22% to 27 +/- 22%; p = 0.10), whereas segments with >75% TEI did not improve (4 +/- 14% to -9 +/- 14%; p = 0.54).

CONCLUSIONS

Drug-eluting stent implantation for a CTO has a beneficial effect on left ventricular volumes and function that can be predicted by performing MRI before revascularization.

A Novel Technique to Detect Total Occlusion in the Right Coronary Artery Using Retrograde Flow by Transthoracic Doppler Echocardiography

BACKGROUND

We hypothesized that detection of reverse flow in the distal right coronary artery (d-RCA) and the inferior septal branches (ISB) by transthoracic Doppler echocardiography (TTDE) would be useful for noninvasive diagnosis of the occluded right coronary artery (RCA).

METHODS

Coronary angiography and TTDE were performed on 129 patients. Antegrade flows in the d-RCA and the ISB were defined as directions from the base to the apex in the posterior sulcus and from anterior to inferior in the inferior septum, respectively. Retrograde flow was defined as an inverse direction.

RESULTS

Retrograde flow was obtained by TTDE in 14 patients (d-RCA:11, ISB:3) of 18 patients with occluded RCA. The sensitivity and the specificity for identification of occluded RCA were 100% and 97.8%, respectively.

CONCLUSION

Detection of reverse flow in the d-RCA and the ISB using TTDE is a useful method for the noninvasive diagnosis of occluded RCA.

Collaterals and the recovery of left ventricular function after recanalization of a chronic total coronary occlusion

BACKGROUND

A good collateral function in patients with regional myocardial dysfunction may indicate viability with the potential for left ventricular (LV) recovery after revascularization of a chronic total coronary occlusion (CTO).

METHODS

A CTO (duration > 2 weeks) was successfully recanalized in 126 patients. During this procedure, the collateral function was assessed before the first balloon inflation by intracoronary Doppler and pressure wires. Collateral function indexes were calculated. Left ventricular function was assessed by the LV ejection fraction (LVEF) and the wall motion severity index (WMSI [SD/chords]). A repeat angiography was available in 119 patients after 4.9 +/- 1.4 m. An improvement of WMSI > or =1 SD/chord was considered significant.

RESULTS

Left ventricular function was normal in 42%, regional dysfunction with LVEF > or = 0.60 was observed in 16%, and regional dysfunction with LVEF < 0.60 in 42%. The former had a better collateral function than patients with LV dysfunction. In 39% of patients with LV dysfunction, a significant myocardial recovery was observed at follow-up. The collateral function was similar in patients with and without recovery. However, patients with recovery had a lower peripheral resistance as an indicator of a better preserved microvascular integrity.

CONCLUSIONS

Recovery of impaired LV function after revascularization of a CTO is not directly related to the quality of collateral function, as collateral development does not appear to require the presence of viable myocardium. However, a preserved microvascular integrity may be of relevance for myocardial recovery.

Recovery of impaired microvascular function in collateral dependent myocardium after recanalisation of a chronic total coronary occlusion

OBJECTIVE

To assess the potential for recovery of impaired microvascular function in collateral dependent myocardium after recanalisation of a chronic total coronary occlusion and the determinants of this recovery.

PATIENTS AND DESIGN

120 patients underwent a successful recanalisation of a chronic total coronary occlusion (duration > 2 weeks) and a follow up angiography after a mean (SD) of 5.0 (1.2) months. The coronary flow velocity reserve (CFVR) and the fractional flow reserve were measured after recanalisation and at follow up. Global and regional left ventricular (LV) function were analysed by quantitative angiography.

RESULTS

Microvascular dysfunction, defined by a CFVR < 2.0 and a fractional flow reserve > or = 0.75, was observed in 55 (46%) patients after recanalisation. Microvascular function improved during follow up in 24 (20%). The CFVR increased during follow up from 2.01 (0.58) to 2.50 (0.79) (p < 0.001), due to a decrease in basal average peak velocity from 30.7 (14.9) cm/s to 25.5 (13.3) cm/s (p = 0.001). Improved microvascular function was associated with an improved regional LV function, shown by a correlation between increased wall motion severity index and increased CFVR (r = 0.38, p = 0.003). The major determinant of microvascular dysfunction at baseline was the presence of diabetes mellitus (odds ratio 4.3, 95% confidence interval 1.8 to 10.2), which remained so at follow up (odds ratio 4.1, 95% confidence interval 1.3 to 13.4). Improvement of LV function was not impaired by the presence of microvascular dysfunction after recanalisation.

CONCLUSIONS

The frequently observed microvascular dysfunction after recanalisation of a chronic total coronary occlusion is a transient phenomenon in most patients and is influenced by the presence of diabetes mellitus. It does not impede the recovery of LV function. Improved regional LV function is associated with improved microvascular function.

Utility of the Safe-Cross-guided radiofrequency total occlusion crossing system in chronic coronary total occlusions (results from the Guided Radio Frequency Energy Ablation of Total Occlusions Registry Study)

The Safe-Cross radiofrequency guidewire (IntraLuminal Therapeutics, Carlsbad, California) combines 3 capabilities: (1) steerability of a conventional 0.014-in intermediate-stiffness guidewire, (2) optical coherence reflectometry to warn the operator when the wire tip approaches within 1 mm of the vessel wall, and (3) delivery of radiofrequency energy pulses to the wire tip to facilitate passage through an occluded segment. The Guided Radio Frequency Energy Ablation of Total Occlusions Registry was a prospective, nonrandomized, multicenter registry that enrolled 116 patients who had long-term coronary total occlusions and in whom a >10-minute good-faith attempt to cross the occlusion using conventional guidewires had failed. The median known duration of occlusion was 22 months (32%; >1 year), and the median length of the occluded segment was 25 mm (25%; >30 mm). Device success was achieved in 63 of 116 of patients (54.3%), and major adverse events occurred in 6.9%, consisting predominantly of isolated increases in cardiac enzymes with no procedure-related deaths, Q-wave myocardial infarctions, or emergency bypass operations. Clinical perforation occurred in 2.6% of patients; of these, perforation in only 1 patient (0.9%) was adjudicated to be directly related to the Safe-Cross radiofrequency wire rather than to the stiff and/or hydrophilic wires used after an inability to advance with the Safe-Cross. Based on these data, the device has been approved in Europe and was recently (January 2004) granted 510K clearance by the Food and Drug Administration.

Delayed recovery of left ventricular function after recanalization of a chronic coronary occlusion

An unusually prolonged course of recovery of severely impaired left ventricular (LV) function (EF 32%) was observed in a patient after recanalization of a chronically occluded LAD. Despite persistent vessel patency, LV function remained depressed for almost 2 years after the percutaneous transluminal coronary angioplasty until complete recovery (EF 82%) could be observed. The possibility of a delayed recovery should be considered when assessing new therapeutic strategies to improve LV function of chronically ischemic myocardium.

Effect of recanalization of chronic total occlusions on global and regional left ventricular function in patients with or without previous myocardial infarction

Previous studies have demonstrated improvement of regional wall motion and global left ventricular function after successful recanalization of chronic total occlusion in coronary artery. However, the difference of benefits of recanalization between infarct site and noninfarct site is unknown. This study assessed the changes in left ventricular ejection fraction, regional wall motion after successful angioplasty of chronic total occlusions with or without previous myocardial infarction. This study also evaluated the factors that influenced the outcome of left ventricular function. We retrospectively studied 75 patients with a successfully recanalized chronic total occlusion in native coronary artery. Left ventriculograms were obtained at baseline and after 6 months. Global and regional left ventricular function were determined. The patients were divided into two groups. Group 1 comprised patients without previous myocardial infarction in the territories of total occlusion vessel that was recanalized. Group 2 comprised patients with previous myocardial infarction in the territories of total occlusion vessel that was recanalized. Left ventricular ejection fraction increased from 53.2% +/- 16.3% at baseline to 57.3% +/- 20.1% at 6-month follow-up in the whole group (P = 0.001). In group 1 patients, the evolution of left ventricular (LV) ejection fraction increased from 59.5% +/- 13.7% to 67.3% +/- 14.6% (P < 0.001). In group 2 patients, the evolution of LV ejection fraction increased, but not significantly, from 48.9% +/- 16.2% to 50.5% +/- 16.9% (P = NS). The evolution of LV ejection fraction increased from 47.6% +/- 17.4% to 50.8% +/- 17.5% (P < 0.05) in the subgroup of recanalization in infarct-related vessel that had rich collateral circulation and had long-term patency. The regional wall motion all significantly improved in group 1 patients (P < 0.05). The regional wall motion did not change in group 2 patients (P = NS). The influence of recanalization of chronic coronary occlusions on the improvement of left ventricular global function was different between myocardial infarction and nonmyocardial infarction patients. The left ventricular function did not improve in myocardial infarction patient. Regional wall motion improved in patients without previous myocardial infarction. For reliable improvement of left ventricular function after recanalization of chronic total occlusions, evidence (not only by symptom or treadmill test) of viable myocardium in recanalized vessel is important. It is also important to keep patency of infarct-related vessel that has good collateral circulation for improving the left ventricular function.

Determinants of target vessel failure in chronic total coronary occlusions after stent implantation. The influence of collateral function and coronary hemodynamics

OBJECTIVES

The goal of this study was to assess the influence of collateral function, coronary hemodynamics, and the angiographic result on the risk of target vessel failure (TVF) after recanalization of a chronic total coronary occlusion (CTO).

BACKGROUND

Collaterals may have an adverse effect on TVF.

METHODS

In 111 consecutive patients, a CTO (duration >2 weeks) was successfully recanalized with stent implantation. Collateral function was assessed by intracoronary Doppler flow velocity and pressure recordings distal to the occlusion. Baseline collateral function was determined before the first balloon inflation, and recruitable collateral function after stenting during a balloon reocclusion. Finally, the coronary flow velocity reserve (CFVR) and the fractional flow reserve (FFR) were measured.

RESULTS

Angiographic follow-up after 5 +/- 4 months in 106 patients showed a reocclusion in 17% and a restenosis in 36%. The major determinants of TVF were the stent length (p < 0.01) and number of implanted stents (p < 0.01). No difference was observed in baseline or recruitable collateral function between patients with and without TVF; 52% of patients had a CFVR >or= 2.0, and only 18% a CFVR >or=2.5 after percutaneous transluminal coronary angioplasty, but neither cutoff-value predicted TVF. A low FFR discriminated patients with reocclusion (0.81 +/- 07 vs. 0.86 +/- 08, p < 0.05) but not with restenosis (0.87 +/- 0.06).

CONCLUSIONS

This study showed that there is no relation between a well-developed collateral supply and the risk of TVF in recanalized CTOs. This was rather determined by the stented segment length. There was also no adverse effect of the frequently observed impaired CFVR on TVF, whereas a low FFR was associated with a higher risk of reocclusion.

[Recanalization of chronic coronary occlusions]

Recanalization of occluded coronary arteries is the aim of percutaneous interventions with acute myocardial infarction. Moreover, chronic coronary occlusion is a common finding during diagnostic coronary angiography and is often a contributing factor in the choice of revascularisation by surgery rather than by percutaneous coronary interventions (PCI). An occluded coronary artery with some degree of collateral supply is functionally comparable to a severe coronary stenosis. Therefore, recanalization of chronic occluded coronary arteries results in less angina and often in improvement of left ventricular function. Success is limited in particular in longer lasting occlusions. Characterization of lesions, where recanalization can performed successfully is warranted. We correlated primary success rates of attempted coronary recanalizations with localisation of lesions and procedural characteristics. We analyzed records of 124 consecutive patients, who underwent attempted coronary recanalization of chronically occluded coronary arteries at our institution in 1998. Revascularisation was successful in 84 (64 male, 20 female) of 124 (92 male, 32 female) patients. Therefore, success rate was 67.7% (69.9% in men, 62.5% in women, p = 0.42). Target vessel was the left anterior descending artery (LAD) in 49 cases. Success rate in the LAD did not differ significantly from that in "non-LAD"-vessels (65.3% versus 69.3%; p = 0.35). Successful recanalizations were performed using only one guide-wire in 77.3%. More than one guide-wires were used during procedures without success in 44.5% and exceeded use in successful interventions (p < 0.05). Procedures, failing to be successful after an attempt with a first guide-wire, could be performed successfully using at least a second wire in 50%. Coronary stenting after recanalization has been performed in 84.4% in the LAD and in 59.7% in non-LAD vessels (p < 0.01). Success rate of attempted recanalizations of chronic occluded coronary arteries in unselected patients is high. Most procedures can be performed successfully using only one guidewire. Additional use of other wires can increase success rates in procedures with primary failure to pass the occlusion. Stenting has been performed in three out of four patients with successful recanalization of chronically occluded coronary arteries.

Noninvasive detection of total occlusion of the left anterior descending coronary artery with transthoracic Doppler echocardiography

OBJECTIVES

The purpose of this study was to evaluate the value of transthoracic Doppler echocardiography (TTDE) for the noninvasive detection of total left anterior descending coronary artery (LAD) occlusion.

BACKGROUND

Total coronary occlusion is associated with an adverse long-term prognosis, and mechanical revascularization may be required for the patient with total coronary occlusion. However, a noninvasive diagnosis of total coronary occlusion before coronary angiography (CAG) has been difficult, especially in patients without clinical signs.

METHODS

We studied 103 consecutive patients who underwent CAG for the evaluation of coronary artery disease. The study group consisted of 16 patients with total LAD occlusion (group A) and 87 patients without total LAD occlusion (group B). Coronary flow velocity in the mid-portion of the LAD was recorded by TTDE.

RESULTS

Adequate spectral Doppler recordings of diastolic flow in the LAD were obtained in 98 study patients (95%; 15 patients in group A and 83 patients in group B). In group A, retrograde LAD flow was obtained in 14 (93%) of 15 patients. The mean diastolic velocity of the retrograde flow was 21.0 +/- 6.1 cm/s. In group B, antegrade LAD flow was obtained in all 83 patients (100%). The mean diastolic velocity of the antegrade flow was 21.5 +/- 7.1 cm/s. Retrograde LAD flow by TTDE had a sensitivity of 93% and a specificity of 100% for the detection of total LAD occlusion.

CONCLUSIONS

Retrograde flow in the LAD by TTDE is a highly sensitive and specific finding that can be used to noninvasively diagnose total LAD occlusion.