RCA Group Research Articles

Citrate anticoagulation and systemic heparin anticoagulation during continuous renal replacement therapy among critically-ill children

BakcgroundThe aim of this study was to evaluate the efficacy and safety of citrate versus heparin anticoagulation for CRRT in critically-ill children.MethodsThis retrospective comparative cohort reviewed the clinical records of critically-ill children undergoing CRRT with either RCA or systemic heparin anticoagulation. The primary outcome measure was hemofilter survival time. Secondary outcomes included the comparison of complications and metabolic disorders.ResultsA total of 131 patients (55 RCA and 76 systemic heparin) were included, in which a cumulative number of 280 hemofilters were used (115 in RCA with 5762 h total CRRT time, and 165 in systemic heparin with 6230 h total CRRT time). Hemofilter survival was significantly longer for RCA (51.0 h; IQR: 24–67 h) compared to systemic heparin (29.5 h; IQR, 17–48 h) (p = 0.002). Clotting-related hemofilter failure occurred in 9.6% of the RCA group compared to 19.6% in the systemic heparin group (p = 0.038). Citrate accumulation occurred in 4 (3.5%) of 115 RCA sessions. Hypocalcemia and metabolic alkalosis episodes were significantly more frequent in RCA recipients (35.7% vs 15.2%, p < 0.0001; 33.0% vs 19.4%, p = 0.009).ConclusionRCA is a safe and effective anticoagulation method for CRRT in critically-ill children and it prolongs hemofilter survival.ImpactRCA is superior to systemic heparin for the prolongation of circuit survival (overall and for clotting-related loss) during CRRT.These data indicate that RCA can be used to maximize the effective delivery of CRRT in critically-ill patients admitted to the PICU.There are potential cost-saving implications from our results owing to benefits such as less circuit downtime and fewer circuit changes.

Quaternary sedimentation over the Precambrian basement of Borborema Province (NE, Brazil): Tectonic and climatic controls

This study characterizes the existence of Quaternary sediments in the Transversal Zone of the Borborema Province (Northeastern Brazil). The sediments comprise paleosoils, unconsolidated sands and gravel deposits, which overlie Precambrian basement rocks. The new data on these deposits includes sedimentological and stratigraphic aspects, and age definition through quartz optically stimulated luminescence (OSL) method. The outcrops were subdivided in two broad groups (named RL and Rca) referring to nearby towns where the samples were collected. OSL ages from the RL group provided ages between ca. 160.15 ± 38.26ka to 4.30 ± 2.18ka, whereas the sediments in the Rca group present OSL ages from 67.45 ± 18.24ka to 7.67 ± 2.74ka. The geochronological results reveal that these sediments were deposited during a time period from the Pleistocene to the Holocene. Deposits are chronocorrelated to Post-Barreiras (ca. 74-2ka in age), apart from the Barreiras Formation (ca. 25 to 17Ma in age), by an expressive hiatus in the Northeast Brazil. Our investigation suggest that the sediments, in the study area, are a reworking of crystalline basement and differs genetically from Post-Barreiras in the coastal zone, which are reworked from the Barreiras Formation. The combination of intense humid chemical weathering during the Pleistocene-Holocene influenced the quaternary deposition in the study area. In addition, the regional brittle tectonic reactivation of shear zones also during the Paleogene influenced the space of accommodation that allowed the deposition of these sediments.

Influence of the Single Coronary Vessel on Acute Outcomes of In-Stent CTO Recanalization.

Recanalization of in-stent chronic total occlusion (IS-CTO) is challenging and has resulted in inconsistent results. The aim of our study was to analyze the influence of the individual coronary vessels on the acute outcomes following IS-CTO PCI. This was an observational retrospective study, including 66 patients undergoing recanalization of a CTO. The CTO interventions were performed bi-femoral using 7-French guiding catheters. A composite endpoint summarizing severe complications was evaluated, including emergency coronary artery bypass grafting surgery (CABG) and cardiac death. We subdivided our cohort into three groups (LAD group, LCX group, RCA group). The retrograde technique and the utilization of an extension catheter were used more frequently in patients with a RCA IS-CTO. There was no significant difference between the composite safety endpoints amongst the three groups. Technical success was independent of the involved vessel. Success and complication rates are independent of the occluded vessel. This challenging and complex coronary intervention is feasible and can be carried out in complete safety.

Effect of Coronary Arterial Dominance Post Primary Percutaneous Coronary Artery Intervention (PCI) during Hospital Stay and at 3-Month Follow-up

Background: Coronary vessel dominance, defined by the coronary artery that supplies the posterior descending artery (PDA) and posterolateral branches, influences the relative contribution of the different coronary arteries to the total left ventricular blood flow. This work aimed to evaluate the prognostic value of coronary arterial dominance post primary PCI, during hospital stay and at 3-month follow-up, which include; cardiac mortality, heart failure, non-fatal myocardial infarction, re-vascularization, stroke/TIA and re-admission for ACS. Methods: This prospective observational study included 100 patients a with STEMI who underwent successful primary percutaneous coronary intervention with TIMI III flow and without procedural complications. Patients were divided into 3 groups according to coronary dominance: Right coronary dominant group (RCD), left coronary dominant group (LCD) and balanced coronary dominant group (BCD). All patients were subjected to transthoracic echocardiogram and coronary angiography and Primary percutaneous coronary intervention. Results: Ticagrelor and clopidogrel during hospital stay and on hospital discharge were significantly used more with RCA group than LCX group and LCX &amp; RCA group (P=0.021, 0.012), (P=0.018, 0.014), respectively. GPIIB/IIIA was significantly more used during hospital stay with RCA group than LCX group and LCX &amp; RCA group(P=0.014). Nitrates was significantly used more on hospital discharge with RCA group than LCX group and LCX &amp; RCA group (P&lt;0.001). Conclusions: Coronary arterial domi¬nance showed significant prognostic value in cases of myocardial Infarction after PCI, heart failure in LCX cases and in revascularization, heart failure, and stroke/TIA cases in RCA. Further, readmission for ACS was the most common outcome in all groups after 3-months follow-up.

Electrocardiography Diagnostic Performance in the Assessment of Significant Coronary Artery Disease and its Anatomical site in Comparison with Coronary Angiography among Nigerians: A Pilot Study

Background: Coronary vessel dominance, defined by the coronary artery that supplies the posterior descending artery (PDA) and posterolateral branches, influences the relative contribution of the different coronary arteries to the total left ventricular blood flow. This work aimed to evaluate the prognostic value of coronary arterial dominance post primary PCI, during hospital stay and at 3-month follow-up, which include; cardiac mortality, heart failure, non-fatal myocardial infarction, re-vascularization, stroke/TIA and re-admission for ACS. Methods: This prospective observational study included 100 patients a with STEMI who underwent successful primary percutaneous coronary intervention with TIMI III flow and without procedural complications. Patients were divided into 3 groups according to coronary dominance: Right coronary dominant group (RCD), left coronary dominant group (LCD) and balanced coronary dominant group (BCD). All patients were subjected to transthoracic echocardiogram and coronary angiography and Primary percutaneous coronary intervention. Results: Ticagrelor and clopidogrel during hospital stay and on hospital discharge were significantly used more with RCA group than LCX group and LCX &amp; RCA group (P=0.021, 0.012), (P=0.018, 0.014), respectively. GPIIB/IIIA was significantly more used during hospital stay with RCA group than LCX group and LCX &amp; RCA group(P=0.014). Nitrates was significantly used more on hospital discharge with RCA group than LCX group and LCX &amp; RCA group (P&lt;0.001). Conclusions: Coronary arterial domi¬nance showed significant prognostic value in cases of myocardial Infarction after PCI, heart failure in LCX cases and in revascularization, heart failure, and stroke/TIA cases in RCA. Further, readmission for ACS was the most common outcome in all groups after 3-months follow-up.

Clinical Outcome of Patients with Acute Inferior Wall Myocardial Infarction: Comparative Study between Left Circumflex Artery and Right Coronary Artery as Aculprit Artery

Information available about comparison between inferior wall myocardial infarction (MI) caused by RCA and LCX occlusion is limited. The aim of present study was to compare the difference between outcome of Left Circumflex artery and Right Coronary artery related acute inferior wall myocardial infarction undergoing emergency percutaneous coronary intervention. This prospective, observational, nonrandomized study enrolled 200 consecutive patients with inferior wall STEMI .The study was done at the National Heart Institute(NHI) and Benha university hospital (BUH),Cairo, Egypt in the period from January 2018 to March 2020.All patients were treated with emergency percutaneous coronary intervention during hospitalization and clinical characteristics and outcomes were compared .Group 1 included 100 patients presented with acute inferior wall STEMI caused by RCA occlusion and Group 2 included 100 patients presented with acute inferior wall STEMI caused by LCX occlusion .In –hospital mortality ,reinfarction, bleeding and stroke were reported in all patients.Total primary outcome in the present study was higher in LCX group(p=0.048) that may be related to higher use stents. Heart failure, stroke and bleeding were more than RCA group. More cardiac enzyme release in LCX group(p=0.046),also regard the 30 days outcome , the current study shows a higher incidence of combined end point of adverse cardiovascular events (Death and re-infarction) in LCX group compared to RCA group but not reaching statistically significance. Conclusions: The results of the current study suggest that LCX related acute inferior STEMI had an unfavorable clinical outcome after emergency PCI compared to RCA related acute inferior STEMI mostly related to relative increase in major or minor bleeding ,stroke and reinfarction.

Prospective evaluation of the development of contrast-induced nephropathy in patients with acute coronary syndrome undergoing rotational coronary angiography vs. conventional coronary angiography: CINERAMA study

Introduction and objectivesRotational coronary angiography (RCA) requires less contrast to be administered and can prevent the onset of contrast-induced nephropathy (CIN) during invasive coronary procedures. The aim of the study is to evaluate the impact of RCA on CIN (increase in serum creatinine ≥0.5mg/dL or ≥25%) after an acute coronary syndrome. MethodsFrom April to September 2016, patients suffering acute coronary syndromes who underwent diagnostic coronary angiography, with the possibility of ad hoc coronary angioplasty, were prospectively enrolled. At the operator's discretion, patients underwent RCA or conventional coronary angiography (CCA). CIN (primary endpoint), as well as analytical, angiographic and clinical endpoints, were compared between groups. ResultsOf the 235 patients enrolled, 116 patients received RCA and 119 patients received CCA. The RCA group was composed of older patients (64.0±11.8 years vs. 59.7±12.1 years; p=0.006), a higher proportion of women (44.8 vs. 17.6%; p<0.001), patients with a lower estimated glomerular filtration rate (76±25 vs. 86±27ml/min/1.73m2; p=0.001), and patients who underwent fewer coronary angioplasties (p<0.001) compared with the CCA group. Furthermore, the RCA group, received less contrast (113±92 vs. 169±103ml; p<0.001), including in diagnostic procedures (54±24 vs. 85±56ml; p<0.001) and diagnostic-therapeutic procedures (174±64 vs. 205±98ml; p=0.049) compared with the CCA group. The RCA group presented less CIN (4.3 vs. 22.7%; p<0.001) compared to the CCA group, and this finding was maintained in the regression analysis (Adjusted relative risk: 0.868; 95% CI: 0.794–0.949; p=0.002). There were no differences in clinical endpoints between the groups. ConclusionsRCA was associated with lower administration of contrast during invasive coronary procedures in acute coronary syndrome patients, resulting in lower incidence of CIN, in comparison with CCA.

Evaluación prospectiva del desarrollo de nefropatía inducida por contraste en pacientes con síndrome coronario agudo tratados con angiografía coronaria rotacional vs. angiografía coronaria convencional: Estudio CINERAMA

Introduction and objectivesRotational coronary angiography (RCA) requires less contrast to be administered and can prevent the onset of contrast-induced nephropathy (CIN) during invasive coronary procedures. The aim of the study is to evaluate the impact of RCA on CIN (increase in serum creatinine ≥0.5mg/dl or ≥25%) after an acute coronary syndrome. MethodsFrom April to September 2016, patients suffering acute coronary syndromes who underwent diagnostic coronary angiography, with the possibility of ad hoc coronary angioplasty, were prospectively enrolled. At the operator's discretion, patients underwent RCA or conventional coronary angiography (CCA). CIN (primary endpoint), as well as analytical, angiographic and clinical endpoints, were compared between groups. ResultsOf the 235 patients enrolled, 116 patients received RCA and 119 patients received CCA. The RCA group was composed of older patients (64.0±11.8 years vs. 59.7±12.1 years; p=0.006), a higher proportion of women (44.8 vs. 17.6%; p<0.001), patients with a lower estimated glomerular filtration rate (76±25 vs. 86±27ml/min/1.73 m2; p=0.001), and patients who underwent fewer coronary angioplasties (p<0.001) compared with the CCA group. Furthermore, the RCA group, received less contrast (113±92 vs. 169±103ml; p<0.001), including in diagnostic procedures (54±24 vs. 85±56ml; p<0.001) and diagnostic-therapeutic procedures (174±64 vs. 205±98ml; p=0.049) compared with the CCA group. The RCA group presented less CIN (4.3 vs. 22.7%; p<0.001) compared to the CCA group, and this finding was maintained in the regression analysis (Adjusted relative risk: 0.868; 95% CI: 0.794-0.949; p=0.002). There were no differences in clinical endpoints between the groups. ConclusionsRCA was associated with lower administration of contrast during invasive coronary procedures in acute coronary syndrome patients, resulting in lower incidence of CIN, in comparison with CCA.

Aorto-ostial atherosclerotic coronary artery disease—Risk factor profiles, demographic & angiographic features

BackgroundThe risk factors along with demographic and angiographic features associated with aorto-ostial atherosclerotic coronary artery disease usually differ from that of non-aorto-ostial atherosclerotic coronary artery disease. ObjectivesThis study was designed to evaluate etiology of aorto-ostial atherosclerotic coronary artery disease involving left main coronary artery (LMCA), right coronary artery or both with consideration of clinical risk factors, demographic and angiographic features. MethodsA total of 7356 angiograms over 2years in continuation were analyzed. Results116 patients were found to have aorto-ostial coronary artery disease with prevalence of 1.5. A total of 95 patients who have complete data were analyzed. Mean age was 59±10years. Prevalence in males was 5.7 times greater than female. Isolated ostial LMCA was 2 times more prevalent than isolated ostial RCA. Hypertension, diabetes and smoking were the main risk factors. 34.7% of the patients had hypercholesterolemia (>180mg/dl) and 26.3% of the patients had hypertriglyceridemia (>150mg/dl). High TC/HDL (>3.5) ratio was seen in 77.9% of the patients. When ostial LMCA group was compared with ostial RCA group hypertriglyceridemia (Odds ratio 9.8, 95% CI, 1.7–4.2, P<0.001) and hypercholesterolemia (Odds ratio 7.05, 95% CI, 1.7–5.7, P<0.001) emerged as independent risk factors for ostial LMCA disease. ConclusionOverall there is 1.5% prevalence of atherosclerotic aorto-ostial disease of coronary arteries among patients of atherosclerotic coronary artery disease and higher proportions of patients are of male sex. Hypercholesterolemia, hypertriglyceridemia and high TC/HDL ratio can be considered as risk factors for aorto-ostial atherosclerotic coronary artery disease.

Ischemia detection from morphological QRS angle changes

In this paper, an ischemia detector is presented based on the analysis of QRS-derived angles. The detector has been developed by modeling ischemic effects on the QRS angles as a gradual change with a certain transition time and assuming a Laplacian additive modeling error contaminating the angle series. Both standard and non-standard leads were used for analysis. Non-standard leads were obtained by applying the PCA technique over specific lead subsets to represent different potential locations of the ischemic zone. The performance of the proposed detector was tested over a population of 79 patients undergoing percutaneous coronary intervention in one of the major coronary arteries (LAD (n = 25), RCA (n = 16) and LCX (n = 38)). The best detection performance, obtained for standard ECG leads, was achieved in the LAD group with values of sensitivity and specificity of , , followed by the RCA group with , Sp = 94.4 and the LCX group with , , notably outperforming detection based on the ST series in all cases, with the same detector structure. The timing of the detected ischemic events ranged from 30 s up to 150 s (mean = 66.8 s) following the start of occlusion. We conclude that changes in the QRS angles can be used to detect acute myocardial ischemia.

Safety and efficacy of early application of tirofiban in STEMI patients undergoing primary percutaneous coronary intervention

ObjectiveTo explore the safety and efficacy of early application of tirofiban in STEMI patients undergoing primary percutaneous coronary intervention (PCI).MethodsFrom September 2008 to march 2011, 157 STEMI patients who were...

The delayed activation wave in non-ST-elevation myocardial infarction

BackgroundLittle is known about the relationship between the electrocardiographic characteristics and the infarct related artery (IRA) in non-ST-elevation myocardial infarction (NSTEMI). We found a curious phenomenon in electrocardiograms of patients with acute occlusion of left circumflex artery in NSTEM: A notch or deflection was often present in the terminal QRS complex in leads II,III and aVF or I,aVL . The objective of this study was to determine whether the previously unreported ECG phenomenon that we have found in NSTEMI could identify the culprit artery in non-ST-elevation myocardial infarction. Methods and ResultsOur study included 218 NSTEMI patients who presented to our institution and underwent coronary angiography within 24 hours of admission. For convenience, ‘N’ wave was defined as a notch or deflection in the terminal QRS complex of the surface ECG. The duration of QRS with N wave before PCI was more prolonged than the duration of QRS without N wave (121±12ms vs 106±11ms, P<0.01). In the LCX group, 66(77%) patients had N wave in leads II, III and aVF, whereas only 5(6%) patients in the LAD group and 9(18%) patients in the RCA group had such ECG feature (P<0.001). A greater proportion of patients in the LCX group also had N waves in leads I and aVL (P<0.001). N wave in leads II, III and aVF was associated with 77% sensitivity and 89% specificity, respectively. N wave in leads I and aVL was associated with 64% sensitivity and 96% specificity, respectively. ConclusionThe abnormal waveform in terminal QRS complex in NSTEMI ,which is described above, is the delayed activation wave of left ventricular basal region which the left circumflex artery supplies. It is associated with a higher specificity and higher sensitivity for culprit LCX in non-ST-elevation myocardial infarction. The delayed activation wave is a new pattern of ischemia in ECG.

Variable ECG signs of ischemia during controlled occlusion of the left and right coronary artery in humans

Infarct size (IS) increases with vascular occlusion time, area at risk for infarction, lack of collateral supply, absence of preconditioning, and myocardial demand for O2 supply. ECG S-T segment elevation is used as a measure of severity of ischemia and a surrogate for IS. This study in 50 patients with coronary artery disease undergoing a first 120-s balloon occlusion of a stenosis sought to determine whether S-T segment elevation, corrected for the above-mentioned variables, in the left coronary artery (LCA group, n = 36) is different from that in the right coronary artery (RCA group, n = 14) territory. After consideration of all known determinants of IS, particularly mass at risk and collateral supply, the LCA territory is more sensitive than the RCA region to a 2-min period of myocardial ischemia.

Reverse remodeling after endoventricular circular patch plasty in the mid-term period

It has been reported that surgical repair of anterior left ventricular (LV) aneurysms is associated with reverse remodeling and improved myocardial function in the inferior LV wall. We evaluated wall motion in RCA territory using QGS in the mid-term period after endoventricular circular patch plasty (EVCPP). Eighteen patients, who underwent EVCPP, were studied by QGS before, and in the early and mid-term periods after surgery. Ten patients underwent CABG to the RCA because of RCA lesions (group B) and the other 8 patients did not have CABG to the RCA (group N). Regional wall thickening function was evaluated by the change in wall thickness through end-systole and end-diastole. We evaluated the RCA territory remote from the incision line of the EVCPP. Regional wall thickness improved significantly in the mid-term period after EVCPP in both groups. Although preoperative wall thickness was worse in group B than in group N, postoperative wall motion in group B was improved as well as in group N in the mid-term period. Inferior LV wall motion improved in patients with and without CABG in the mid-term period. We conclude that reverse remodeling occurred in the mid-term period after EVCPP.

Sirolimus-eluting stent treatment for isolated proximal left anterior descending artery stenoses

Stenting of isolated proximal LAD stenoses is still a controversial issue since it is associated with higher target vessel revascularization (TVR) rate than both bypass surgery using the internal mammary artery, and stenting of other coronary artery territories. The sirolimus- eluting stent (SES) has been reported to significantly reduce restenosis rates in de novo coronary lesions. Therefore, we compared patients from the German Cypher Registry treated with SES for isolated proximal LAD lesions with those stented for isolated lesions in the proximal LCX or RCA. A total of 349 patients treated with SES were analyzed. 249 patients were treated for proximal LAD stenosis, and 100 for proximal LCX/RCA stenoses. The combined clinical endpoint was MACCE (death of any cause, non-fatal MI and non-fatal stroke) and TVR at 6 months. In-hospital events (death, MI and TVR) did not differ significantly between both groups (3.2% for the LAD group vs 2.0% for the LCX/RCA-group, p=0.73). The combined end point of death of any cause, non-fatal MI and non-fatal stroke at six months was 2.6% in the LAD group, and 2.2% in the LCX/RCA group (p=1.0). TVR occurred in 4.8% of the LAD group and in 6.5% of the LCX/RCA group at six months (p=0.58). The percentage of patients free from angina at daily activities was 80.6% in the LAD group, and 77.4% in the LCX/ RCA group (p=0.52). SES once implanted into isolated proximal LAD stenoses appears as effective as reported in other vessel territories. Accordingly, stenting of the proximal LAD using SES might prove a suitable alternative to surgery.

The Source of Inflammatory Response and Platelet Activation in Patients with Acute Myocardial Infarction

Background and Objectives:Studies on the stability of atheromatous plaques, as a determinant of the cause of complications, have been reported. Among the functional features of plaques related with vulnerability, inflammation has emerged as a leading cause of clinical presentation. The purpose of this study was to find the source of the inflammatory response in the patients with acute myocardial infarction (AMI). Subjects and Methods:Patients with AMI, whose lesion of in either the left anterior descending artery (LAD group, n=13) or the right coronary artery (RCA group, n=11), were selected. The levels of interleukin-6 (IL-6) and P-selectin were measured in blood from the aortic root (A), great cardiac vein (G) and peripheral vein (V). The control group (n=15) included patients with either stable or variant angina. Results:The levels of IL-6 were 4.77±6.0 (A), 11.32±7.8 (G) and 4.39±5.0 pg/mL (V) in the LAD group, and 3.64±2.1 (A), 6.05±4.9 (G) and 3.84±3.2 pg/mL (V) in the RCA group. Unrelated to the infarction related artery, the level of IL-6 in the great cardiac vein was significantly increased in patients with AMI. The percentages of platelet expressed P-selectin were 6.03±7.0 (A), 8.14±8.1 (G) and 8.83±7.9 (V) in the LAD group and 6.46±8.4 (A), 5.80±6.0 (G) and 5.91±6.9 (V) in the RCA group. Conclusion:These findings suggest that the generalized inflammatory response is activated across the coronary vascular bed in patients with AMI, regardless of the infarction related artery site. Therefore, systemic therapy, as well as local management for vulnerable plaque, would be required. (Korean Circulation J 2005;35:155-162)

Comparison of culprit lesions showing negative remodeling between acute coronary syndrome and stable angina pectoris

between RCA and control group (p=O.lO). Conclusions: Coronary sinus blood temperature measurement is increased compared to that of right atrium in patients with significant lesions in LCA. This technique may prove useful in identifying patients with enhanced inflammatory involvement and additional studies are required for evaluating the clinical significance of coronary sinus thermography in risk stratification and prognosis.

Recording locations in multichannel magnetocardiography and body surface potential mapping sensitive for regional exercise-induced myocardial ischemia.

This study aimed to identify the optimal locations in multichannel magnetocardiography (MCG) and body surface potential mapping (BSPM) to detect exercise-induced myocardial ischemia. We studied 17 healthy controls and 24 coronary artery disease (CAD) patients with stenosis in one of the main coronary artery branches: left anterior descending (LAD) in 11 patients, right (RCA) in 7 patients, and left circumflex (LCX) in 6 patients. MCG and BSPM signals were recorded during a supine bicycle stress test. The capability of a recording location to separate the groups was quantified by subtracting the mean signal amplitude of the normal group from that of the patient group during the ST segment and at the T-wave apex, and dividing the resulting amplitude difference by the corresponding standard deviation within all subjects. In MCG the optimal location for ST depression was at the right inferior grid for the RCA, at the mid-inferior grid for the LCX, and in the middle of these locations for the LAD subgroup (mean ST amplitudes: CAD -80 +/- 360fT, controls 610 +/- 660fT; p < 0.001). In BSPM it was on the left upper anterior thorax for the LAD, left lower anterior thorax for the RCA, and on the lower back for the LCX subgroup (mean ST amplitudes: CAD -39 +/- 61 microV and controls 38 +/- 38 microV; p < 0.001). In MCG the optimal site for T-wave amplitude decrease was the same as the one for the ST depression. In BSPM it was on the middle front for the LAD, on the back for the LCX and on the left abdominal area for the RCA group. In accordance with electromagnetic theory, the largest ST segment and T-wave amplitude changes took place in MCG in locations orthogonal to those in BSPM. This study identified magnetocardiographic and BSPM recording locations which are sensitive for detecting transient myocardial ischemia by evaluation of the ST segment as well as the T-wave. These locations strongly depend on ischemic regions and are outside the conventional 12-lead ECG recording sites.

Negative u wave during percutaneous transluminal coronary angioplasty

To clarify the clinical significance of the negative U wave during acute myocardial ischemia, the appearance of the U wave and ST-segment elevation on electrocardiography during percutaneous transluminal coronary angioplasty (PTCA) of the left anterior descending artery (LAD group: 11 patients) or right coronary artery (RCA group: 18 patients) was studied. During PTCA, U-wave inversion (newly developed negative U wave, and increased negativity of the pre-existing negative U wave) was observed in 37 (90%) of 41 patients in the LAD group and in 16 (89%) of 18 patients in the RCA group. The incidence of ST-segment elevation was similar to that of U-wave inversion; however, U-wave inversion appeared before detectable ST-segment elevation in 20 patients (49%) in the LAD group and in 4 patients (22%) in the RCA group. Moreover, U-wave inversion was observed frequently in a wider range of leads than ST-segment elevation. These results suggest that the U wave is a more sensitive indicator of myocardial ischemia than ST-segment elevation in some patients, and that a negative U wave may be produced by a different mechanism than that which produces ST-segment deviation, although both are related to myocardial ischemia.

脳底動脈瘤へのapproach

Two routes in the pterional approach to the distal basilar artery aneurysms have been known: one is via the space between the optic nerve and the internal carotid artery (opticcarotid triangle: OCT), and the other is lateral to the ICA (retrocarotid approach: RCA). Although the approach via the OCT has several advantages of its own, it had been considered applicable to very limited cases. We successfully clipped such aneurysms via OCT in four cases out of 12 cases (33%), and the neuroradiological findings observed in these cases are analyzed and reported.Measurements were made on the following items on the carotid angiogram of the cases operated via the OCT (OCT group) and the RCA (RCA group): the distance of ICA bifurcation from the midline (D) and the height of ICA bifurcation from the baseline between the anterior and posterior clinoid processes (H). Although these two values seemed to be higher in the OCT than in the RCA group, no significant difference was found. The product of D and H (D×H) was observed to be significantly higher in the OCT than in the RCA group. The value of D×H is considered one of the indicate of the size of the OCT and has proved to be useful in judging whether the approach via the OCT is applicable or not.The approach via the OCT has several advantages, such as no injury to the oculomotor nerve, less retraction to the ICA and easy visualization of the P1 segment of the opposite side. The space of the OCT can be used not only for clipping itself but also as a line of sight to the deep structures as well as clips applied from other routes.