Development of a sensitive enzyme-linked immunosorbent assay for measurement of DNase I in human serum.

BACKGROUND: Serum deoxyribonuclease I (DNase I) activity was reported to increase in the early phase after onset of acute myocardial infarction (AMI). Up to now, DNase I activity has been quantified by the single radial enzyme diffusion (SRED) method, which unfortunately requires a long incubation time. Therefore it is necessary to develop another assay suitable for measurement of serum DNase I concentrations in a clinical setting. METHODS: A sandwich ELISA was established for measurement of DNase I protein using a polyclonal antibody directed against DNase I protein and a biotinylated monoclonal for subsequent detection. Concentrations of serum DNase I protein were measured in healthy individuals and patients with AMI. RESULTS: This method was as precise as SRED, and took less time than SRED. A significant correlation was observed between DNase I concentration and enzyme activity (r=0.839; P<0.001). The average of serum DNase I in AMI patients within 0-12 h of chest pain was significantly higher than that in healthy individuals (P<0.001), and decreased with time. CONCLUSIONS: We have developed a sensitive ELISA capable of measuring DNase I protein concentrations. This method may be a useful alternative to SRED as an aid to diagnosis of AMI based on the serum DNase I level.

Impact of lesion calcification on clinical and angiographic outcome after sirolimus-eluting stent implantation in real-world patients.

BACKGROUND: Previous studies have demonstrated similar efficacy of the drug-eluting stent (DES) in patients with and without calcified lesions. However, most of the randomized trials have excluded patients with severe calcified lesions. This study aimed to examine the impact of lesion calcium on clinical and angiographic outcome after sirolimus-eluting stent (SES) implantation in real-world patients. METHODS: Consecutive 380 patients with 556 lesions treated with SES were enrolled. Lesions were divided into Calc lesions (moderate or sever calcification; 195 lesions) and non-Calc lesions (none or mild calcification; 361 lesions) according to the lesion calcium. Quantitative coronary angiography (QCA) parameters, binary restenosis rate (%restenosis), target lesion revascularization (TLR) rate, and major adverse cardiac events (MACE) during follow-up were compared between the two groups. All patients were contacted at 1, 6, and 12 months after the procedure. RESULTS: Lesion success rate was similar in the two groups. %Restenosis (9.2% vs. 3.6%; P<.05) and TLR (7.3% vs. 2.8%; P<.05) were significantly higher in Calc lesions. Stent thrombosis was observed in 0.7% of overall lesions with no difference between the two groups. The MACE rate in Calc patients (13.8%) was significantly higher than in non-Calc patients (6.1%). By multivariate analysis, hemodialysis (HD) and requirement of rotational atherectomy (RA) were predictive factors of TLR in the Calc lesions. CONCLUSIONS: Coronary lesions with calcification comprise a high-risk cohort and are associated with a higher TLR and binary restenosis rates in real-world patients treated with SES. Moreover, patients with calcified lesions and on HD are associated with higher MACE rate.

Usefulness of virtual histology intravascular ultrasound to predict distal embolization for ST-segment elevation myocardial infarction.

OBJECTIVES: We aimed to predict the high-risk plaque of distal embolization after stent deployment in patients with acute ST-segment elevation myocardial infarction (STEMI) with Virtual Histology intravascular ultrasound (VH-IVUS) (Volcano Therapeutics, Inc., Rancho Cordova, California). BACKGROUND: Distal embolization during primary percutaneous coronary intervention (PCI) carries a poor prognosis in patients with STEMI. However, it is unclear which plaque characteristics cause distal embolization after stent deployment. METHODS: A total of 71 patients with STEMI were included prospectively. All patients underwent primary PCI within 12 h of symptom onset. After crossing the lesion with a guidewire and performing thrombectomy with an aspiration catheter, VH-IVUS of the infarct-related vessel was performed. Stent deployment was then undertaken without embolic protection. ST-segment re-elevation (STR) was used to evaluate distal embolization. Correlations among plaque characteristics, morphology, and distal embolization were analyzed. RESULTS: The STR after stent deployment was observed in 11 patients (STR group, 15.5%). Necrotic core volume was significantly higher in the STR group than in the non-STR group (32.9 +/- 14.1 mm3 vs. 20.4 +/- 19.1 mm3, p < 0.05). Total plaque volume was similar in both groups. On receiver-operating characteristic analysis, necrotic core volume clearly predicted STR after stent deployment as compared with fibrous, fibro-lipid, dense calcium, and total plaque volumes. The necrotic core volume that was best predictive for STR was 33.4 mm3, with a sensitivity of 81.7% and a specificity of 63.6%. CONCLUSIONS: Virtual Histology IVUS is a useful means of predicting the risk of distal embolization after primary stent deployment in patients with STEMI.

Prognostic impact of ventilatory efficiency in heart disease patients with preserved exercise tolerance.

BACKGROUND: The minute ventilation/carbon-dioxide output (VE/VCO2) slope as a marker of cardiac events has been established in patients with severe heart failure, but it is not known whether it is useful for other heart diseases. METHODS AND RESULTS: The present study investigated 215 patients with various heart diseases (age 59+/-11 years; ischemic heart disease, n=89; dilated cardiomyopathy, n=38; valvular disease, n=37; hypertensive heart disease, n=33; others, n=18) who underwent cardiopulmonary exercise testing to determine the VE/VCO(2) slope. Patients were divided into 2 groups according to the VE/VCO2 slope and were followed-up for 3 years. Forty-eight cardiac events (6 deaths, 42 re-hospitalizations) occurred during the observation period. Patients with a VE/VCO2 slope >34 had a significantly higher 3-year cardiac event rate (32.1%) than patients with VE/VCO2 slope <34 (18.9%, p<0.05). When patients were selected with relatively preserved peak oxygen uptake values (>16 ml . kg (-1) . min(-1)), patients with VE/VCO2 slope >34 still demonstrated a significantly higher cardiac event rate than other patients (35.0% vs 13.3%, p<0.01). CONCLUSION: The VE/VCO2 slope may be a prognostic indicator of cardiac events in a heterogeneous group of patients with heart disease, independent of exercise tolerance.

Usefulness of quantitative gated single-photon emission computed tomography to evaluate ventricular synchrony in patients receiving biventricular pacing.

Quantitative gated single-photon emission computed tomography was performed in 10 patients before and shortly after (<1 month) receiving biventricular pacing (BVP). They were divided into 2 groups (responder and nonresponder groups) on the basis of clinical status and echocardiographic parameters 18 +/- 6 months later. In the responder group, left ventricular synchrony shortly after BVP improved significantly compared with that before BVP (p <0.05), but there was no change in the nonresponder group.

[Comparison of clinical and angiographic outcomes between S670 and NIR stents].

OBJECTIVES: This study evaluated the long-term outcomes of successfully implanted S670 and NIR stents. METHODS: Stents were successfully implanted in 143 patients (148 lesions) aged 65 +/- 9 years from January 1999 to April 2001. Sixty-eight lesions were treated with S670 stents and 80 with NIR stents. Quantitative coronary angiography was performed before, immediately after and 6 months after implantation. An angiographic classification of in-stent restenosis was developed according to the geographic distribution of intimal hyperplasia in reference to the implanted stent. Furthermore, the relationships between stent diameter and length and restenosis rate were estimated. RESULTS: Type B2/C lesions were significantly more common in patients with S 670 (77.3%) stents compared with NIR (43.6%). Stent length was longer and diameter was smaller in patients with S 670 stents compared with those with NIR stents. Acute-gain was similar in the two groups, but late-loss was significantly greater in patients with S 670 stents compared with those with NIR stents. Restenosis rate and target lesion revascularization rate were similar in the two groups. The diffuse type of restenosis lesion was frequently found in S 670 stents. The stent diameter, but not stent length, influenced the restenosis rate in S 670 stents. Both stent length and diameter influenced the restenosis rate in NIR stents. CONCLUSIONS: Late-loss was larger and in-stent restenosis of diffuse type was significantly greater in S 670 stents compared with NIR stents. However, stent length was significantly longer and type B2/C lesions were significantly greater in S 670 stents compared with NIR stents. There was no difference in restenosis rate and target lesion revascularization rate. In addition, restenosis rate was not influenced by stent length in S 670 stents, so S 670 stents may be useful for complex lesions.

[Clinical significance of exercise-induced ST segment depression in patients with lateral myocardial infarction involving the left circumflex artery: evaluation by exercise 99mTc-MIBI myocardial scintigraphy].

PURPOSE: The aim of this study is to clarify the causes of exercise-induced ST-segment depression in patients with broad lateral old myocardial infraction involving LCX (LCX-OMI) without ischemia on exercise scintigraphy. METHOD: Twenty one patients (M/F = 11/10, age = 62 +/- 19 years) with myocardial infraction involving LCX (LCX-MI), but without fill-in on exercise and rest MIBI quantitative gated SPECT (QGS), were selected. They were divided into two groups of Group ST(+) (n = 11, with significant ST depression (max -2.8 +/- 0.4 mm), Group ST(-) (n = 10) without ST depression. On 20 SPECT segments of both exercise and rest SPECT, we scored uptake score as DS (0 = normal to 3 = defect) and wall motion as WMS (0 = normal to -5 = dyskinesis) and summed DS (TDS) and WMS (TWMS) in LCX region, furthermore, calculated the difference of TWMS (delta TWMS [exercise-rest]), end diastolic volume (EDV) and ejection fraction (EF) during exercise were compared between the two groups. RESULT: Group ST(+) showed significantly (p < 0.01) lower EF (35.4 +/- 9.2% vs. 60.2 +/- 6.2%), larger EDV (146 +/- 53 ml vs. 93 +/- 15 ml), higher TDS (5 vs. 7 +/- 3), lower TWMS (-25 +/- 9 vs. -6 +/- 5), furthermore lower delta TWMS (-6.9 +/- 4.0 vs. -2.0 +/- 0.8) than Group ST(-). CONCLUSION: Exercise-induced significant ST depression in V2-4 without ischema in LCX-MI was observed in patients with broad LCX-MI, low EF, and was related to impaired wall motion in LCX region. ST depression in V2-4 was considered to appear as miller image of ST elevation at postero-inferior wall due to disturbed wall motion on exercise.