Correlation between fractional flow reserve and intravascular ultrasound lumen area in intermediate coronary artery stenosis

AIMS

Fractional flow reserve (FFR) of <0.8 or 0.75 is currently used to guide revascularisation in lesions with intermediate coronary stenosis. We assessed whether there is an intravascular ultrasound (IVUS) measurement that can reliably be used to predict when patients should undergo intervention.

METHODS AND RESULTS

The analysis included 92 intermediate lesions (84 patients) located in vessel diameters >2.5 mm. Positive FFR was considered present at <0.8 and 0.75. IVUS minimum lumen area (MLA) was correlated to the FFR findings in intermediate lesions with 40-70% stenosis. The mean FFR value was 0.89 ± 0.08. Twenty-four patients (26.1%) had FFR <0.8; 17 (18.5%) <0.75. Positive correlations between FFR and IVUS measurements included MLA (r = 0.34, p<0.001), minimum lumen diameter (MLD) (r=0.31, p=0.004), lesion length (r=-0.5, p<0.001), and area stenosis (r=-0.31, p=0.01). There was no significant correlation between FFR and quantitative coronary angiography in MLD (r=0.19, p=0.06), diameter stenosis (r=0.08, p=0.4), or lesion length (r=-0.14, p=0.17). A receiver operating characteristic curve identified MLA <2.8 mm2 (sensitivity 79.7%, specificity 80.3%) as the best threshold value for FFR <0.75; and MLA <3.2 mm2 as best for FFR <0.8 (sensitivity 69.2%, specificity 68.3%).

CONCLUSIONS

Anatomic measurements of intermediate coronary lesions obtained by IVUS show a moderate correlation to FFR values, although they differ according to vessel size. IVUS MLA may be used as an alternative to FFR when assessing the need for intervention in intermediate coronary lesion. Vessel size, however, should always be taken into account.

Hybrid strategy of a bare metal stent combined with a drug-eluting stent versus exclusive drug-eluting stent implantation for multivessel percutaneous coronary intervention

AIMS

This study aimed to examine the strategy of hybrid percutaneous coronary intervention (PCI) -bare metal stent (BMS) and drug-eluting stent (DES)- versus exclusive DES implantation for patients undergoing multivessel PCI.

METHODS AND RESULTS

A cohort of 2,065 patients who underwent PCI (698 hybrid, 1,367 exclusive DES) were followed clinically up to one year. The primary outcome was target vessel revascularisation-major adverse cardiac events (TVR-MACE). Patients presenting with cardiogenic shock, anaemia (haematocrit <25), and bypass graft PCI were excluded. Only patients with ≥ 2 stents in two different lesions were analysed for this study. Baseline and procedural characteristics were similar. Major in-hospital complications and subacute stent thrombosis rates were similar. At one year, there was no difference in TVR-MACE (hybrid 17.2% vs. DES 14.6%, p=0.128). On multivariable analysis, hybrid PCI was not a predictor of TVR-MACE. The strongest predictors of TVR-MACE at one year were hypertension and African American race. Cumulative stent thrombosis rates at one year were similar in both groups.

CONCLUSIONS

Patients who undergo hybrid PCI have similar composite in-hospital and 1-year outcomes as those who undergo exclusive DES PCI. The hybrid stent approach should be considered for patients with multivessel PCI since it can lower the procedure cost without increasing adverse events.

Cellular video-phone assisted transmission and interpretation of prehospital 12-lead electrocardiogram in acute st-segment elevation myocardial infarction

BACKGROUND

Prehospital 12-lead electrocardiogram (ECG) reduces the time to reperfusion in acute ST-segment elevation myocardial infarction (STEMI). However, the reliability of using cellular video-phone (VP) assisted interpretation of ECG is unknown.

METHODS

We studied the interphysician reliability in interpreting the ECG assisted with VP compared to print ECG interpretation. Twenty-seven physicians prospectively interpreted the ECG transmitted from the field in real-time using VP and later using the same printed ECG. The time to completion, accuracy of interpretation, and physician rating of the VP technology were recorded.

RESULTS

Similar high interphysician reliability was observed with both VP assisted and printed ECG interpretation including presence of ST-segment elevation (intraclass correlation coefficient [ICC]= 0.98 [95% CI 0.96-1] vs. 0.99 [95% CI 0.99-1]) and pathologic Q wave (ICC = 0.99 [95% CI 0.98-1] vs. 1 [95% CI 1]), respectively. The mean time to transmit and interpret the ECG with VP versus printed ECG was 3.9 ± 1.9 versus 2.1 ± 0.9 minutes, respectively, P < 0.01. On a scale of 1 to 5 with 5 being the best, the average rating of VP ease of use was 4.4 ± 0.5 and utility to recommend treatment was rated a 5.

CONCLUSION

Cellular VP-assisted transmission and interpretation in real-time of prehospital ECG has high interphysician reliability, similar to the printed ECG interpretation. Future studies testing whether VP decreases the ischemic time and expedites the reperfusion of STEMI patients are needed.

Outcomes after unrestricted use of everolimus-eluting stent compared to paclitaxel- and sirolimus-eluting stents

Compared to paclitaxel-eluting stents (PESs) and sirolimus-eluting stents (SESs), a paucity of data exists regarding the clinical outcome of everolimus-eluting stents (EESs) in unselected patients with the entire spectrum of obstructive coronary artery disease. The present study cohort included 6,615 consecutive patients at Washington Hospital Center who underwent coronary artery stent implantation with EESs (n = 519), PESs (n = 2,036), or SESs (n = 4,060). Patients who received bare metal stents, zotarolimus-eluting stents, or 2 different drug-eluting stent types were excluded. The analyzed clinical end points were death, death or Q-wave myocardial infarction, target lesion revascularization (TLR), target vessel revascularization, definite stent thrombosis, and major adverse cardiac events, defined as the composite of death, Q-wave myocardial infarction, or TLR at 1 year. The groups were well matched for the conventional risk factors for coronary artery disease, except for systemic hypertension, which differed among the groups. The unadjusted end points for EESs and PESs were death (4.5% vs 7.1%; p = 0.03), TLR (3.4% vs 4.6%; p = 0.24), target vessel revascularization (5.6% vs 7.1%; p = 0.46), death or Q-wave myocardial infarction (4.5% vs 7.4%; p = 0.02), and definite stent thrombosis (0.0% vs 0.7%; p = 0.09). The unadjusted end points for EES and SES were death (4.5% vs 5.2%; p = 0.45), TLR (3.4% vs 5.8%; p = 0.3), target vessel revascularization (5.6% vs 8.6%; p = 0.05), death or Q-wave myocardial infarction (4.5% vs 5.4%; p = 0.39), and definite stent thrombosis (0.0% vs 1.08%; p = 0.003). The rates of major adverse cardiac events were similar among the 3 groups. After multivariate analysis, the rate of death or Q-wave myocardial infarction between the EES and PES groups was no longer significant (hazard ratio 1.14, 95% confidence interval 0.59 to 2.20, p = 0.70). In conclusion, the results of the present study suggest the use of EES in routine clinical practice is both safe and effective but offers no clinically relevant advantage in terms of hard end points compared to PES or SES.

Sirolimus-eluting stents versus paclitaxel-eluting stents in patients with chronic renal insufficiency

BACKGROUND

Chronic renal insufficiency (CRI) is associated with an increased incidence of restenosis and stent thrombosis. Drug-eluting stents (DES), when compared to bare metal stents (BMS), reduce the incidence of restenosis in these patients. This study aimed to examine whether there are differences in clinical outcome after implantation of sirolimus-eluting stents (SES) versus paclitaxel-eluting stents (PES) in patients with CRI who are subjected to coronary intervention.

METHODS

A cohort of 570 patients with CRI who underwent intervention with DES (346 with SES and 224 with PES) were followed clinically up to 1 year and the clinical events were recorded and compared between groups.

RESULTS

Baseline and procedural characteristics were similar, with a slightly higher number of diseased vessels in the SES group as compared to the PES group (2.3 +/- 0.9 vs 2.1 +/- 0.9, P = 0.06). The overall rates of major adverse cardiac events (MACE) and stent thrombosis were similar. The PES group had lower revascularization rates when compared to the SES group. After covariate adjustment, however, there was no difference seen in target vessel revascularization between stent types (hazard ratio [HR]: 2.3 [0.8-6.2], P = 0.110). The strongest predictor of death and MACE at 1 year was the number of diseased vessels.

CONCLUSIONS

Patients with CRI who undergo PCI with either SES or PES have similar repeat revascularization rates and acceptable stent thrombosis rates, although they continue to have high MACE and death rates.

Left ventricular contraction patterns in patients with suspected acute coronary syndrome and normal coronary angiograms: a new look at the takotsubo syndrome

BACKGROUND

Original descriptions of the takotsubo syndrome (TS) included a characteristic left ventricular (LV) contraction pattern, "apical ballooning." Recently, several reports have associated contraction patterns not strictly conforming to the original description with TS. The specifics of the contraction pattern seem to set TS apart from the much larger population of patients with acute coronary syndrome (ACS) but no obstructive coronary artery disease (OCAD). This study was undertaken to compare patients with midventricular and apical dysfunction with those with other LV contraction patterns.

HYPOTHESIS

If TS can present with a variety of patterns of LV dysfunction, then both those with and those without the pattern should have the clinical components previously assigned to the syndrome.

METHODS

We studied LV contraction patterns in consecutive ACS patients referred for consideration of emergent or urgent percutaneous coronary intervention.

RESULTS

Of the 893 patients evaluated in 2008, we excluded 862 on the basis of OCAD, preexisting LV dysfunction, or an obvious alternative cause of symptoms. The remaining 31 (3.5%) also had no OCAD but manifested an LV contraction abnormality. We compared the 15 patients (1.7%) whose ventriculograms met criteria for TS with the 16 patients (1.8%) whose did not. The most common alternative pattern was global hypokinesis, followed by a variety of segmental contraction abnormalities. Patients with the TS pattern were older and had evidence of greater myocardial injury. More than 85% were women.

CONCLUSIONS

The TS pattern identifies a distinct subset of ACS patients with a remarkable predominance of postmenopausal women and is therefore fundamental to the definition of this entity. This distinctive facet of the syndrome is likely to be an important clue to its pathogenesis. We did not encounter patients with other patterns of LV dysfunction that could be thought to represent stress-induced cardiomyopathy. Copyright © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.