Characteristics of patients and types of lesions in patients with drug-eluting or bare-metal stent implantation in small coronary arteries

Clinical utility of intravascular ultrasonography-guided therapy in a small-vessel coronary lesion associated with Type 2 diabetes mellitus

Objective:

It is unknown whether the intravascular ultrasound (IVUS) guidance for percutaneous coronary intervention (PCI) should be routinely used in small-vessel coronary lesions in patients affected by Type 2 diabetes mellitus (T2DM). This study aimed to assess the clinical significance of the IVUS-guided PCI treatment for small-vessel coronary lesions in T2DM.

Methods:

This was a prospective interventional trial. A total of 228 patients affected by T2DM with stable angina and a positive stress test in the presence of coronary arteriography (CAG) involving small vessels [online measurement reference vessel diameter ≤3.0 mm by means of quantitative coronary angiography (QCA)] were recruited and divided into two groups: an IVUS-guided group (n=120) and a CAG-guided group (n=108). Follow-up PCIs were performed via CAG or IVUS criteria, respectively. Between-group comparisons were made for the number of stents implanted, length, diameter, and high-pressure balloons used post-dilatation. Major adverse cardiac events (MACEs) defined as cardiac death, nonfatal myocardial infarction, and target lesion revascularization (TLR) were the primary endpoint. The value of late lumen loss and proportion of in-stent restenosis (ISR) were the secondary endpoint, all of which were also evaluated during the follow-up period.

Results:

There was an increased lesion length observed using the IVUS measurement when compared with QCA measurements in the IVUS-guided group (p≤0.001). The number of implanted stents, diameter, length, percentage of high-pressure balloons used during post-dilatation, value of late lumen loss, and proportion of ISR decreased in the IVUS-guided group when compared with the CAG-guided group (p=0.002, p=0.001, p=0.003, p=0.004, p=0.007, p=0.001, respectively). After a 2-year follow-up, the Kaplan–Meier curves indicated that the incidence of MACEs was significantly lower in the IVUS-guided group (log-rank p=0.029), mainly because of the TLR reduction (log-rank p=0.037).

Conclusion:

The IVUS-guided PCI treatment improved the event-free survival in small-vessel coronary lesions in patients affected by T2DM.

Atherosclerotic Coronary Artery Disease in Patients With Cardiometabolic Syndrome

Major risk factors for cardiovascular disease (CVD) include aging, gender, smoking, family history and cardiometabolic syndrome. The relative residual risks for CVD after statin treatment for primary and secondary prevention have been reported by several large-scale randomized clinical trials. Statin treatment appears to prevent one-third of the onset and progression of CVD, but not the remaining two-thirds. There are three major problems regarding the residual risk of CVD: 1) Insufficient reduction of low-density lipoprotein cholesterol levels; 2) Low levels of high-density lipoprotein cholesterol and elevated triglyceride; and 3) Insufficient control of other risk factors (high blood pressure, obesity, metabolic syndrome, type 2 diabetes, etc.). Thus, a multifaceted preventive approach should be needed to prevent CVD after statin treatment.

Initial and late efficacy of everolimus-eluting stents for small and non-small coronary lesions from evaluating delayed late loss study

The aim of the present study was to evaluate the long-term outcomes at 2 years in patients in whom everolimus-eluting stents (EESs) were implanted in small and non-small vessels. A small vessel is an important risk factor for restenosis with BMSs, even in the first generation DESs. The 690 patients with 690 lesions implanted with an EES were enrolled and divided into two groups by vessel reference diameter (RD): >2.5 mm for non-small vessels (Non-S-group) and ≤2.5 mm for small vessels (S-group). Two years later, the 365 patients with no restenosis at 8 months who underwent angiography were enrolled into the late catch-up study. At the initial 8-month follow-up, the rates of restenosis and target lesion revascularization (TLR) of both groups were not significantly different (restenosis 3.9 vs 6.5%, p = 0.17; TLR 3.9 vs 6.5%, p = 0.17). At the late 2-year follow-up, there were no significant differences in the late loss (0.36 ± 0.66 vs 0.34 ± 0.50 mm, p = 0.14), net gain (1.50 ± 0.75 vs 1.26 ± 0.60 mm, p = 0.39), late catch-up restenosis rate (5.1 vs 3.4%, p = 0.38), TLR (4.9 vs 2.7%, p = 0.40), and delayed late loss (0.14 ± 0.58 vs 0.15 ± 0.49 mm, p = 0.10) between both groups. There is no correlation between delayed late loss and RD in all patients(r = -0.009) and in AMI patients (r = -0.004). These results demonstrate that the initial and late catch-up restenosis rates of small coronary vessels with EES placement were excellent, the same as for non-small coronary vessels. We suggest that involvement of small coronary arteries may not be a risk factor for restenosis and results of stenting for small coronary arteries with EES placement were excellent.

Preprocedural Albumin Levels and Risk of In-Stent Restenosis After Coronary Stenting With Bare-Metal Stent

In-stent restenosis (ISR) remains a significant clinical problem in patients with coronary artery disease treated with percutaneous coronary intervention. Decreased serum albumin (SA) level is related to an increased risk of cardiovascular events. The aim of the present study was to assess whether SA levels at admission are an independent predictor of ISR in patients undergoing bare-metal stent (BMS) implantation. A total of 341 patients (aged 61 ± 11, 65.4% men) with a history of BMS implantation and a further control coronary angiography due to stable angina pectoris (SAP) were included. The study population was classified into 2 groups: patients with and without ISR. The ISR was observed in 140 (41.1%) patients. We found significantly lower SA levels in patients who developed ISR than in those who did not (3.69 ± 0.41 vs 4.07 ± 0.35 mg/dL,P< .001). Multivariate analysis revealed that SA level (odds ratio 0.109, 95% confidence interval 0.017-0.700,P= .020), stent diameter, reason for stent implantation, and body mass index were independent risk factors for the development of ISR. The SA level at admission is inversely associated with ISR in patients with SAP.

Clinical utility of low-pressure implantation of drug-eluting stent into very small vessels

BACKGROUND

Although drug-eluting stents (DES) reduce restenosis, the best strategy for DES implantation in small vessels has not been established.

PURPOSE

We investigated the clinical usefulness of low-pressure implantation of a 2.5-mm DES for small vessels less than 2.5mm in diameter.

METHODS

In 118 patients, a 2.5-mm DES was implanted for small vessels less than 2.5mm in diameter between 2007 and 2009 in our hospital. The patients were divided into two groups by initial deployment pressure: low-pressure (LP; n=46) and nominal-pressure (NP; n=72).

RESULTS

Patients with impaired glucose tolerance were more frequent (p=0.02) and the target vessel diameter was significantly smaller (p=0.01) in the LP group than in the NP group. A smaller minimum lumen diameter (MLD) was obtained (LP: 2.22±0.27mm vs. NP: 2.34±0.26mm, p=0.02) after DES implantation with a smaller balloon-to-artery ratio (p=0.03) in the LP group. However, at mid-term follow-up (7.7±3.9 months), MLD (p=0.55) and the binary restenosis rate (LP: 2.6% vs. NP: 11.1%, p=0.12) were not significantly different between the LP and NP groups. Furthermore, by Kaplan-Meier analysis, the incidence of major adverse cardiac events was not different between the groups during the long-term follow-up (32.4±8.6 months).

CONCLUSION

The present study indicates that low-pressure implantation of 2.5-mm DES for very small vessels may be feasible with regard to short- and long-term clinical outcomes.

Clinical outcomes of everolimus- and zotarolimus-eluting stents in patients with acute myocardial infarction for small coronary artery disease

BACKGROUND AND PURPOSE

There were limited data about comparison of zotarolimus-eluting stents (ZES) and everolimus-eluting stents (EES) in patients with small coronary artery disease (CAD), especially in patients with acute myocardial infarction (AMI). The objective of this study was to compare the clinical outcomes of ZES and EES in patients with AMI for small CAD.

METHODS AND SUBJECTS

A total 1565 AMI patients treated with Endeavor-ZES (n=651) (Medtronic CardioVascular, Santa Rosa, CA, USA) or Xience V/Promus-EES (n=914) (Abbott Vascular, Temecula, CA/Boston Scientific, Natick, MA, USA) for small CAD (stent diameter ≤ 2.75 mm) in KAMIR (Korea Acute Myocardial Infarction Registry) were enrolled. After propensity score matching to adjust for baseline clinical and angiographic characteristics, we compared a total 1302 patients (651 ZES and 651 EES) about major adverse cardiac events (MACE) at 1-year. Subgroup analysis about 1-year clinical outcomes was undertaken in patients who were discharged alive.

RESULTS

Baseline clinical and angiographic characteristics were similar between the two groups after propensity score matching. Total MACE did not differ between the two groups before (9.8% vs. 8.2%, p=0.265) and after (9.8% vs. 9.4%, p=0.778) propensity score matching. The EES group showed lower rate of 1-year cardiac death (5.4% vs. 3.3%, p=0.041), target lesion failure (TLF; 6.9% vs. 4.3%, p=0.022), and stent thrombosis (1.4% vs. 0.4%, p=0.042) compared with the ZES group. However, there were no differences in 1-year cardiac death, TLF, and stent thrombosis in propensity score matched populations. Other various 1-year clinical outcomes showed no difference between the two groups. Subgroup analysis in patients who were discharged alive showed similar outcomes between the two groups at 1-year follow-up.

CONCLUSION

In-this propensity score matched analysis, EES and ZES showed no significant difference in clinical outcomes at 1-year follow-up in patients with AMI for small CAD.

Association of prediabetes with diffuse coronary narrowing and small-vessel disease

BACKGROUND

A significant number of patients may not benefit from conventional techniques of myocardial revascularization due to diffuse coronary artery disease (CAD) or small coronary arterial sizes because of smaller arteries causing anastomotic technical difficulties and poor run-off. Diabetic patients have a more severe and diffuse coronary atherosclerosis with smaller coronary arteries limiting the possibility to perform a successful and complete revascularization, but this has not been examined in prediabetics.

OBJECTIVE

To evaluate whether there is an association between prediabetes and the coronary arterial size.

METHODS

We prospectively studied 168 consecutive patients with CAD and 172 patients with normal coronary artery anatomy (NCA). Patients were divided into three groups according to hemoglobin (Hb) A1c levels as "normal," "prediabetic," and "diabetic" groups, and the coronary artery sizes and Gensini scores were analyzed.

RESULTS

There were 78 female patients and 90 male patients in the CAD group, and 87 female patients and 85 male patients in the NCA group. There was a statistically significant difference in distal and proximal total coronary arterial size among the CAD and NCA groups for both genders. There was a positive correlation between the HbA1c subgroups and Gensini score (Spearman's ρ: 0.489, p<0.001 in female group; Spearman's ρ: 0.252 p=0.016 in male group).

CONCLUSION

We found that prediabetic patients have a smaller coronary size and diffuse coronary narrowing for both genders, particularly in distal coronary arterial tree of left anterior descending coronary artery. The early detection of prediabetes in daily cardiology practice may provide more appropriate coronary lesion for percutaneous or surgical revascularization.