A two year echocardiographic follow-up of patients with chronic total occlusion treated with percutaneous coronary intervention or receiving only medical therapy

Background

Percutaneous coronary intervention of chronic total occlusion (PCI CTO) can reduce angina and the need for bypass surgery, however, it is still not clear how it effects the myocardial function. Conventional echocardiography is subjective and experience-dependent while tissue Doppler imaging together with strain imaging provides a more objective assessment of myocardial contractility.

Purpose

Our aim was to access the effectiveness of percutaneous coronary intervention (PCI) along with optimal medical therapy (OMT) on myocardial function.

Methods

We compared two groups of patients. The first group of patients underwent PCI CTO with OMT while the second group of patients only received OMT (control group). The echocardiographic exam was performed before randomization and after 24 months of follow-up. Doppler time intervals- isovolumetric relaxation time (IVRT), isovolumetric contraction time (IVCT) and ejection time (ET) were measured from mitral inflow and left ventricular outflow Doppler tracings. Myocardial performance index (MPI) is equal to the sum of the IVRT and IVCT divided by the ET. Velocity of early mitral filling wave (E) was measured and divided by average peak early diastolic annular velocity (e'). Peak longitudinal strain was assessed in 17 left ventricular segments. Time intervals from start Q/R on electrocardiogram to peak negative strain during the cardiac cycle were assessed. Mechanical dispersion was defined as the standard deviation of this time interval from 17 left ventricular segments, reflecting myocardial contraction heterogeneity

Results

Comparing the groups at follow up, there was no significant change in ejection fraction (EF), diastolic function, and mechanical dispersion, however, there was improvement in GLS and MPI (Table 1).

Conclusion

Global longitudinal strain as a parameter of systolic function and Myocardial performance index as a parametar of global systolic and diastolic function are sensitive markers that can detect subtle improvement in myocardial function after recanalisation of CTO.

Funding Acknowledgement

Type of funding source: None

Impairment of coronary flow velocity reserve and global longitudinal strain in women with cardiac syndrome X and slow coronary flow

BACKGROUND

Microvascular dysfunction (MVD) is associated with adverse prognosis and may account for abnormal stress tests and angina symptoms in women with cardiac syndrome X (CSX). The aim of our study was to assess MVD by coronary flow velocity reserve (CFVR) and left ventricular (LV) contractile function by LV global longitudinal strain (LVGLS) in CSX patients with respect to presence of slow coronary flow (SCF). It was of additional importance to evaluate clinical status of CSX patients using Seattle Angina Questionnaire.

METHODS AND RESULTS

Study population included 70 women with CSX (mean age 61 ± 7 years) and 34 age-matched controls. CSX group was stratified into two subgroups depending on SCF presence: CSX-Thrombolysis In Myocardial Infarction (TIMI) 3- normal flow subgroup (n = 38) and CSX-TIMI 2- SCF subgroup (n = 32) as defined by coronary angiography. LVGLS measurements and CFVR of left anterior descending (LAD) and posterior descending (PD) artery were performed. CFVR-LAD and PD were markedly impaired in CSX group compared to controls (2.34 ± 0.25 vs 3.05 ± 0.21, p < 0.001; 2.32 ± 0.24 vs 3.01 ± 0.13, p < 0.001), and furthermore decreased in CSX-TIMI 2 patients. Resting, peak, and ΔLVGLS were all significantly impaired in CSX group compared to controls (for all p < 0.001), and furthermore reduced in CSX-TIMI 2 subgroup. Strongest correlation was found between peak LVGLS and CFVR LAD (r = -0.784, p < 0.001) and PD (r = -0.772, p < 0.001). CSX-TIMI 2 subgroup had more frequent angina symptoms and more impaired quality of life.

CONCLUSIONS

MVD in CSX patients is demonstrated by reduction in CFVR and LVGLS values. SCF implies more profound impairment of microvascular and LV systolic function along with worse clinical presentation.

P3125Five-year impact of immediate invasive strategy on clinical outcomes in patients with non-ST-segment elevation myocardial infarction: RIDDLE-NSTEMI study

Background

Most of the previous studies evaluated the impact of early versus delayed invasive intervention on clinical outcomes in patients with non-ST segment elevation acute coronary syndrome (NSTE-ACS) in one-year period.

Purpose

The aim of this study was to assess whether the immediate invasive intervention influences the occurrence of death and new myocardial infarction (MI), specifically in patients with non-ST segment MI (NSTEMI) in long-term follow-up.

Methods

In The Randomized Study of Immediate Versus Delayed Invasive Intervention in Patients With Non ST-segment Elevation Myocardial Infarction (RIDDLE-NSTEMI) 323 patients with NSTEMI were randomized to either immediate (median time to intervention was 1.4 hours) or delayed invasive strategy (61.0 hours). The incidence of primary outcome -death or new MI at 30 days was lower in patients assigned to the immediate (n=162) than in patients assigned to the delayed (n=161) invasive intervention group (4.3% vs. 13%, respectively; p=0.008). Long-term follow-up of 5 years was available for 96.90% of the patients.

Results

At 5 years, the immediate invasive intervention was associated with lower rate of death or new MI, compared with delayed invasive strategy (15.8% vs 32.9%, respectively; p=0.00). The observed benefit of the immediate intervention was mainly due to an increased early reinfarction risk with the delayed strategy (2.5% vs 9.9%, p=0.001) with similar new MI rates beyond 30 days (5.9% in the immediate and 10.7% in the delayed group, p=0.130). Five-year mortality was 12.0% in the immediate invasive intervention strategy group, and 18.1% in the delayed strategy group (p=0.135).

Conclusion

Immediate invasive intervention in the patients with NSTEMI significantly reduces the early risk of new MI. However, the timing of invasive intervention appears not to have significant impact on the clinical outcome beyond 30 days.

Prognostic Value of Preserved Coronary Flow Velocity Reserve by Noninvasive Transthoracic Doppler Echocardiography in Patients With Angiographically Intermediate Left Main Stenosis

BACKGROUND

The potential of angiography to evaluate the hemodynamic severity of a left main coronary artery (LM) stenosis is limited. Noninvasive transthoracic Doppler echocardiographic coronary flow velocity reserve (CFVR) evaluation of intermediate coronary stenosis has demonstrated remarkably high negative prognostic value. The aim of this study was to assess clinical outcomes in patients with angiographically intermediate LM stenosis and preserved CFVR (>2.0) as evaluated by transthoracic Doppler echocardiographic CFVR.

METHODS

The initial study population included 102 patients with intermediate coronary stenosis of the LM referred for transthoracic Doppler echocardiographic CFVR assessment. Peak diastolic CFVR measurements were performed in the distal segment of the left anterior descending coronary artery after intravenous adenosine (140 μg/kg/min), and CFVR was calculated as the ratio between maximal hyperemic and baseline coronary flow velocity. Nineteen patients had impaired CFVR (≤2.0) and were excluded from further analysis, as well as two patients with poor acoustic windows. The final group consisted of 81 patients (mean age, 60 ± 9 years; 76 men) evaluated for adverse cardiac events including death, myocardial infarction, and revascularization.

RESULTS

Mean follow-up duration was 62 ± 26 months. Mean CFVR was 2.4 ± 0.4. Total event-free survival was 75 of 81 (92.6%), as six patients were referred for revascularization (five patients with coronary artery bypass grafting, one patient with percutaneous coronary intervention). There were no documented myocardial infarctions or cardiovascular deaths in the follow-up period.

CONCLUSIONS

In patients with angiographically intermediate and equivocal LM stenosis and preserved CFVR values of >2.0, revascularization can be safely deferred.

Prognostic value of calcium score and coronary flow velocity reserve in asymptomatic diabetic patients

BACKGROUND

The risk stratification of patients with diabetes mellitus (DM) is a major objective for the clinicians, and it can be achieved by coronary flow velocity reserve (CFVR) or with coronary artery calcium score (CS). CS evaluates underlying coronary atherosclerotic plaque burden and CFVR estimates both presence of coronary artery stenosis and microvascular function. Consequently, CFVR may provide unique risk information beyond the extent of coronary atherosclerosis.

AIM

Our aim is to assess joint prognostic value of CFVR and CS in asymptomatic DM patients.

MATERIALS AND METHODS

We prospectively included 200 asymptomatic patients (45,5 % male, mean age 57,35 ± 11,25), out of which, there were 101 asymptomatic patients with DM and 99 asymptomatic patients without DM, but with one or more conventionally risk factors for coronary artery disease. We analyzed clinical, biochemical, metabolic, inflammatory parameters, CS by Agatston method, transthoracic Doppler echocardiography CFVR of left anterior descending artery and echocardiographic parameters.

RESULTS

Total CS and CS LAD were significantly higher, while mean CFVR was lower in diabetics compared to the nondiabetics. During 1 year follow-up, 24 patients experienced cardio-vascular events (one cardiovascular death, two strokes, three myocardial infarctions, nine new onsets of unstable angina and nine myocardial revascularizations): 19 patients with DM and five non DM patients, (p = 0,003). Overall event free survival was significantly higher in non DM group, compared to the DM group (94,9 % vs. 81,2 %, p = 0,002 respectively), while the patients with CS ≥200 and CFVR <2 had the worst outcome during 1 year follow up in the whole study population as well as in the DM group. At multivariable analysis CFVR on LAD (HR 12.918, 95 % CI 3.865-43.177, p < 0.001) and total CS (HR 13.393, 95 % CI 1.675-107.119, p = 0.014) were independent prognostic predictors of adverse events in DM group of patients.

CONCLUSION

Both CS and CFVR provide independent and complementary prognostic information in asymptomatic DM patients. When two parameters are analyzed together, the risk stratification ability improves, even when DM patients are analyzed together with non DM patients. As a result, DM patients with CS ≥200 and CFVR <2 had the worst outcome. Consequently, the use of two tests identified subset of patients who can derive the most benefit from the intensive prevention measures.

Stenting a myocardial bridge: a wrong decision in STEMI?

In a STEMI setting, stent implantation for a myocardial bridge (MB) with significant systolic compression in the mid LAD, is a challenging issue.The risk of coronary rupture during stent implantation arises from: (i) a thin intima of the bridged artery; (ii) a thin myocardial layer toward the right ventricle; (iii) a smaller LAD diameter in the MB; (iv) high inflation pressure in the balloon. Perforation with a coronary fistula resolving spontaneously within several months is one of the possible scenarios. We report a case of a coronary fistula between mid LAD and right ventricle after MB stenting in a patient with STEMI, with spontaneous angiographic deterioration after several days. Stent graft implantation in case of a coronary fistula with increasing flow is an effective therapeutic concept.

Systemic rapamycin without loading dose for restenosis prevention after coronary bare metal stent implantation

OBJECTIVES

The aim of this study was to assess the role of short oral administration of rapamycin, without loading dose, in the reduction of restenosis rate after bare metal stent implantation.

BACKGROUND

Previous studies suggest that the administration of oral rapamycin reduces angiographic restenosis after bare metal stent implantation.

METHODS

This was prospective, open-label study of 80 patients randomized to either oral rapamycin (2 mg/day for 30 days, starting within 24 hr of stent implantation) or no therapy after implantation of a coronary bare metal stent. The primary study end point was incidence of angiographic binary restenosis and late loss at six months. The secondary end points were target lesion revascularization (TLR), target vessel revascularization (TVR), and incidence of major adverse cardiovascular events (MACE) at 6 months.

RESULTS

Angiographic follow up was completed in 72/80 (90%) of patients. In the rapamycin group, the drug was well tolerated (22.5% minor side effects) and was maintained in 100% of patients. At six months, the in-segment binary restenosis was 10.5% in rapamycin group vs. 51.4% in no-therapy group, P < 0.001) and the in-stent binary restenosis was 7.9% in rapamycin group vs. 48.7% in no-therapy group, P < 0.001. The in-segment late loss was also significantly reduced with oral therapy (0.29 + or - 0.39 vs. 0.86 + or - 0.64 mm, respectively, P < 0.001). Similarly, after six months, patients in the oral rapamycin group also showed a significantly lower incidence of TLR and TVR (7% vs. 22.7%, respectively, P = 0.039) and MACE (7% vs. 22.7%, respectively, P = 0.039).

CONCLUSIONS

This study showed that the administration of oral rapamycin (2 mg/day, without loading dose) during 30 days after stent implantation significantly reduces angiographic and clinical parameters of restenosis.