Evidence Of Myocardial Ischemia Research Articles

Higher fasting glucose is associated with poorer survival in non-diabetic subjects having ischemia with non-obstructive coronary arteries

Subjects who have ischemia with non-obstructive coronary arteries (INOCA) experience angina pectoris with evidence of myocardial ischemia but without coronary stenosis. Few studies have investigated factors associated with its survival, especially insulin resistance. In this study, subjects with angina pectoris, without known diabetes mellites (DM), and with non-invasive tests showing myocardial ischemia were admitted for coronary angiography (CAG). Those whose CAG did not reveal stenosis and agreed to receive an oral glucose tolerance test (OGTT) 2 weeks after hospital discharge were enrolled for analysis. All-cause mortality was recorded, which served as the outcome of the study. A total of 587 subjects with INOCA, without known DM, and with OGTT data were analyzed. After OGTT and HbA1c tests, 86 subjects (14.7%) were newly diagnosed with DM and 59.8% had pre-DM. The median duration of follow-up was 7.03 years. Thirty-nine subjects died during the follow-up period. The incidence rate of mortality was 9.9 /1000 person-year. Those who died had a higher fasting glucose (101 ± 17 vs. 94 ± 13 mg/dl, p = 0.003) but a lower estimated glomerular filtration rate (eGFR) (54 ± 22 vs. 87 ± 30 ml/min, p < 0.001). In the Cox survival analysis, a higher fasting glucose (hazard ratio 1.053, p = 0.007) was associated with worse mortality for INOCA without DM (N = 501). On the contrary, a higher eGFR (hazard ratio 0.967, p = 0.012) was protective of better survival for non-diabetic INOCA (N = 501). In conclusion, for non-diabetic INOCA, higher fasting glucose was associated with worse mortality and higher eGFR was protective for better survival.

Periprocedural myocardial infarction after percutaneous coronary intervention and long-term mortality: a meta-analysis.

Conflicting data are available regarding the association between periprocedural myocardial infarction (PMI) and mortality following percutaneous coronary intervention. The purpose of this study was to evaluate the incidence and prognostic implication of PMI according to the Universal Definition of Myocardial Infarction (UDMI), the Academic Research Consortium (ARC)-2 definition, and the Society for Cardiovascular Angiography and Interventions (SCAI) definition. Studies reporting adjusted effect estimates were systematically searched. The primary outcome was all-cause death, while cardiac death was included as a secondary outcome. Studies defining PMI according to biomarker elevation without further evidence of myocardial ischaemia ('ancillary criteria') were included and reported as 'definition-like'. Data were pooled in a random-effect model. A total of 19 studies and 109 568 patients were included. The incidence of PMI was progressively lower across the UDMI, ARC-2, and SCAI definitions. All PMI definitions were independently associated with all-cause mortality [UDMI: hazard ratio (HR) 1.61, 95% confidence interval (CI) 1.32-1.97; I2 34%; ARC-2: HR 2.07, 95% CI 1.40-3.08, I2 0%; SCAI: HR 3.24, 95% CI 2.36-4.44, I2 78%]. Including ancillary criteria in the PMI definitions were associated with an increased prognostic performance in the UDMI but not in the SCAI definition. Data were consistent after evaluation of major sources of heterogeneity. All currently available international definitions of PMI are associated with an increased risk of all-cause death after percutaneous coronary intervention. The magnitude of this latter association varies according to the sensitivity and prognostic relevance of each definition.

Successful Retrieval of Rota Burr After Driveshaft Fracture

Rotational atherectomy is an effective procedure for heavily calcified lesions and those that cannot be crossed using conventional percutaneous coronary intervention (PCI) devices. Here, we report a rare case of intracoronary burr entrapment in the coronary artery due to burr disconnection from the driveshaft. A 67‐year‐old man undergoing hemodialysis for nephrosclerosis presented with exertional chest discomfort. Coronary angiography revealed stenotic lesions in the right coronary artery, and PCI was performed using a Rotawire Floppy. During the procedure, the disconnected burr was successfully removed without surgery using the child‐in‐mother technique with a guide extension catheter. Notably, the patient remained hemodynamically stable throughout the procedure and his recovery was uncomplicated. He was discharged on the second postprocedural day. At the 6‐month follow‐up, the patient remained asymptomatic with no evidence of myocardial ischemia. This report informs clinicians of the possibility of burr disconnection and the non‐surgical intervention used for its removal.

Abstract 12538: Myocardial Bridge Induced Cardiomyopathy

Introduction: A myocardial bridge(MB) is a condition in which the epicardial coronary artery traverses through the myocardium, has an intra-myocardial course of varying length, and then exits the myocardium and appears on the surface of the heart. Clinical Presentation: A 54-year-old male with no significant past medical history except tobacco abuse and anxiety presented to the hospital with retrosternal chest pain radiating to the back and shoulder and associated with nausea and diaphoresis. His SBP was 100/60, and his heart rate 46. His EKG showed ST elevation in inferior leads, and he was given a nitro tablet, which improved the chest pain to 5/10. He was emergently taken to the Cath lab and found to have proximal left circumflex artery occlusion and underwent PCI with a 2.25x23 Xience Drug-eluting stent. Troponin was elevated to 2.35. His cath also showed a significant mid-LAD myocardial bridge. His echocardiogram showed mid and apical anterior, anterior septal, apical wall, and inferior wall hypokinesis. His EF has been reduced to 30%. Coronary CTA showed mid-LAD has myocardial bridging, which is more than 2 cm long and 5 mm deep in the muscle. The patient has persistently low HR in 40-45, beta-blocker was not started. Due to significant cardiomyopathy induced by a myocardial bridge, unroofing of LAD was done off-pump. His EF improved to 55% after three months of surgery. Discussion: CABG or myotomy is the treatment of choice for patients with symptomatic myocardial bridging refractory to medical therapy, evidence of myocardial ischemia or infarction, or &gt;75% systolic coronary compression on angiography. Incidental myocardial bridging finding without ischemia or symptoms does not require any treatment. Symptomatic patients with ischemia on stress tests can be offered beta or calcium channel blockers. Medical therapy is superior to revascularization with percutaneous intervention.

Automatic electrocardiograph diagnosis of myocardial ischemia with support vector machine

ABSTRACT Background: Myocardial ischemia is a severe cardiac disease and it happens when the heart's blood flow is insufficient, which impairs its capacity to operate correctly and causes several systemic issues. A standard auxiliary for the clinical diagnosis of myocardial ischemia is an electrocardiograph (ECG). However, the typical static ECG cannot record the myocardial ischemia paroxysmal fragments quickly and accurately. The information contained in long-term ECG recordings is more abundant, but the large volume of data makes manual processing costly. Our aim is to propose an automated method for handling ECG signals and diagnosing myocardial ischemia. Methods: To get evidence of myocardial ischemia, dynamic ECG is frequently employed. This paper suggests a machine learning technique to create a classification model using support vector machine (SVM), automatically identifying the existence of myocardial ischemia fragments. This study comprises waveform identification, feature extraction, creation of data sets, model training, and classification. The Long Term ST Database, made available by PhysioNet, is used as the database for this research. Result: According to the final test results, the classification accuracy is 97.98%. The ECG signals can be automatically segmented, and the automated diagnosis of myocardial ischemia can achieve an accuracy rate of 97.98%. Conclusion: The results suggest that the method proposed in this paper can more precisely and practically identify myocardial ischemia pieces.

O050 Utility of ramp test time in patients undergoing assessment for renal transplantation

Abstract Introduction Prior to renal transplant listing, cardiovascular screening is performed to stratify the risk of cardiovascular disease (CVD). During pre-assessment in our centre, patients undergo a ramp test (a timed assessment to walk 130m), which is a rapid and non-invasive method of quantifying exercise tolerance. The purpose of this study is to correlate ramp test time (RTT) with transplant waiting list status, cardiac stress testing, and post-transplant CV events and mortality. Methods Retrospective analysis of patients that underwent pre-assessment. Data collection included patient demographics, history of CVD and diabetes, RTT, ejection fraction and evidence of myocardial ischaemia, transplant list status, any subsequent CV event, and mortality. Three groups were analysed: (1) patients unable to perform the test; (2) RTT≥2mins; (3) RTT≤1min. Results 1508 patients were pre-assessed for transplantation between 2014-2022. Mean RTT was 86 seconds (SD±26 seconds). Patients with RTT&amp;lt;1min were younger with less pre-existing CVD, of whom 93% had normal cardiac stress testing. Over half of the patients who either had RTT &amp;gt;2mins or were unable to perform the test had abnormal cardiac function, with a 3-year mortality of about 30%. Conclusion RTT can be used to assess cardiovascular suitability for transplantation. Patients unable to perform the test are unlikely to be listed for transplantation, with a quarter suffering a CV event post-assessment. In contrast, patients with RTT≤1min are almost all activated with no subsequent CV events. The low rate of CV events or abnormal stress tests in this group may allow early activation without extensive cardiovascular assessment.

Prevalence of stable coronary artery disease and its associated clinical factors among patients with chest pain and elevated cardiac troponin alone

Cardiac troponin is a useful test for diagnosing cardiogenic causes in patients with chest pain. However, cardiac troponin levels are often elevated in patients with chest pain due to non-cardiac causes other than coronary artery disease. The purpose of this study was to investigate the prevalence of coronary artery disease (CAD) and its associated factors in patients with chest pain and elevated cardiac troponin I (cTnI). 104 patients (mean age, 65 ± 11 years; 60 [58%] men) who underwent coronary angiography (CAG) for chest pain and elevated cTnI levels were enrolled in this study. All patients had a normal CK-MB range and did not show any ischemic changes on electrocardiography or echocardiography. Patients were classified into two groups according to the presence of CAD (Group 1, n = 62) and the absence of CAD (Group 2, n = 42). Patients were classified into subgroups according to the presence (Group 2a, microvascular angina [MVA], n = 18) and absence (Group 2b, non-angina [NA], n = 25) of angina. CAD was diagnosed in 62 (60%) patients and MVA was suspected in 18 (17%) patients without CAD. Patients with CAD showed elevated blood pressure and slightly decreased heart rate. Diabetes mellitus was more prevalent in patients with CAD and patients without CAD (esp. with MVA) were more likely to be common drinkers. Increased relative wall thickness (RWT) and reduced E’ velocity were associated with CAD. High-density lipoprotein (HDL) levels were reduced in patients with CAD and MVA but were higher in patients with NA. Lower HDL level was found to be independently associated with the presence of CAD. Elevated cTn1 levels without other evidence of myocardial ischemia are sufficient for performing CAG in patients with stable chest pain.

Benign Late T Wave Inversion Post Coronary Artery Bypass Grafting: Case Report of Myocardial Reperfusion Sign Appearing Late on ECG

The onset of new T wave inversion (TWI) on an electrocardiogram (ECG) has always been considered an alarming sign of myocardial ischemia. Successful myocardial infarction reperfusion is indicated by the presence of early TWI after revascularization. We report a case of benign late precordial TWI post-coronary artery bypass grafting (CABG) with no evidence of myocardial ischemia.

415 DOES MYOCARDIAL BRIDGING TRIGGER MYOCARDIAL ISCHEMIA?

Abstract Background Myocardial bridging (MB) is a congenital epicardial coronary abnormality, in which a segment of the artery runs through the myocardium, determining dynamic stenosis during systole. Whether MB can be responsible by itself for myocardial ischemia remains unclear. Thus, we aimed to evaluate whether the dynamic stenosis related to MB can cause signs and symptoms of myocardial ischemia. Methods We enrolled 41 consecutive patients who underwent coronary angiography because of chest pain suspected for ischemic heart disease and were found to have MB in the absence of any significant flow-limiting coronary stenosis and any other cardiac disease. A group of 14 patients who also underwent coronary angiography because of chest pain suspected for ischemic heart disease, but found to be free of any coronary or cardiac abnormality (including MB) and also showed negative results at exercise stress test (EST) served as controls. All enrolled patients underwent a maximal treadmill EST according to standard Bruce protocol. A complete echocardiographic examination was performed at rest and at peak exercise. Results Baseline EST parameters were comparable between groups, whereas peak diastolic blood pressure (pDBP) was slightly higher in the MB group (p=0.044). No clinically significant differences were found in baseline echocardiographic parameters, although the E wave deceleration time (DcT) was longer (p=0.038) and global longitudinal strain (GLS) was higher (p=0.05) in the MB group. During exercise, left ventricular ejection fraction (LVEF) improved significantly in both groups (p&amp;lt;0.001), without any difference between the 2 groups. GLS did not show any significant changes with exercise in both groups. Moreover, among MB patients, no differences were found in stress echocardiographic results between those with positive vs. those with negative EST. Conclusions We failed to demonstrate any significant ischemic impairment of LV systolic and diastolic function at maximal EST in patients with MB. Moreover, we also failed to demonstrate any LV dysfunction in MB patients that developed ECG signs of myocardial ischemia during EST, as compared to those without evidence of myocardial ischemia. Thus, our data question about the ability of MB itself to trigger significant myocardial ischemia in clinical practice.

Percutaneous Patent Foramen Ovale Closure in a Patient With Anomalous Aortic Origin of the Left Coronary Artery

Percutaneous Patent Foramen Ovale Closure in a Patient With Anomalous Aortic Origin of the Left Coronary Artery

Ultralow energy cardioversion in a pig model of atrial fibrillation: A feasibility study.

Postoperative atrial fibrillation (POAF) is the most frequent heart rhythm disorder after cardiac surgery.1 Despite improvements in morbidity and mortality associated with cardiac surgery, the incidence of POAF remains largely unchanged. Electrical cardioversion is indicated in patients with POAF who have evidence of myocardial ischemia, infarction, or hemodynamic instability.2 This study evaluated the feasibility and effectiveness of ultralow energy cardioversion through epicardial leads by using the novel external defibrillation interface module (EDIM) called Rhythm Maker (NativeCardio, Inc, Naples, FL).

D-5 | FFR and dFR Correlation at a Single Center

Fractional flow reserve (FFR) is used to determine hemodynamic significance of coronary artery lesions. FFR was validated in a prospective, Bayesian approach where the value of 0.75 was identified to be associated with evidence of myocardial ischemia. FFR, which is based on the ratio between mean distal and proximal coronary pressures during the entire cardiac cycle (including systolic). Since estimation of myocardial flow has a linear relationship only during diastole where myocardial resistance is at its minimum.

Target and non-target vessel related events at 10 years post percutaneous coronary intervention

AimsTo define the incidence of events related to the stented vessel (target vessel related events: TVRE) and events related to non-stented vessels (non-target vessel related events: NTVRE) through to 10-year follow-up in patients post-PCI with newer generation drug eluting stents (DES).Methods and resultsThe current study is a post-hoc analysis of patient level data from two randomised controlled trials in Germany. Patients older than 18 years with ischemic symptoms or evidence of myocardial ischemia in the presence of ≥ 50% de novo stenosis located in the native coronary vessels were considered eligible. The endpoints of interest were TVRE (a composite of first target vessel myocardial infarction or target vessel revascularization) and NTVRE (a composite of first non-target vessel MI or non-target vessel revascularization) through to 10 years post PCI.We included 4953 patients in this analysis. Through to 10-years post-PCI, TVRE occurred in 1238 of 4953 patients (cumulative incidence: 25.8%) and NTVRE occurred in 1442 of 4953 patients (cumulative incidence: 30.3%). The majority of TVRE and NTVRE were revascularization events. From 0 to 1 years, the cumulative incidence of TVRE was 15.9% and of NTVRE was 12.3%. From 1 to 10 years, the cumulative incidences of TVRE and NTVRE were 11.2% and 22.4%, respectively.ConclusionAt 10-year post-PCI with new generation drug eluting stents, events related to remote vessel disease progression account for a higher proportion of events than events related to the stented vessel.Trial registrationISAR TEST 4 ClinicalTrials.gov Identifier: NCT00598676. ISAR TEST 5 ClinicalTrials.gov Identifier: NCT00598533.Graphical abstract

A retrospective cohort study of major adverse cardiac events in children affected by Kawasaki disease with coronary artery aneurysms in Thailand

Kawasaki disease (KD) is a common form of vasculitis in children that can be complicated by coronary artery aneurysms (CAAs). Data of long-term outcomes and major adverse cardiac events (MACE) in children with CAAs following KD in developing country are limited. Our aims were to determine the rates of MACE and identify risk factors associated with MACE in children with KD and CAAs in Thailand. We performed a retrospective analysis of data from 170 children diagnosed with KD and CAAs in two tertiary hospitals between 1994 and 2019. During a median (range) follow-up of 5.4 years (22 days to 23 years), 19 patients (11.2%) experienced MACE, that included 12 coronary artery bypass grafting, 2 percutaneous coronary intervention and 5 children with evidence of myocardial ischemia and coronary occlusion. Coronary interventions were performed at a median time of 4 years (0.01 to 9.5 years) after KD diagnosis. Forty-nine patients (28.8%) had giant CAAs. No MACE was reported in children with small CAAs. Independent risks of MACE were from the absence of intravenous immunoglobulin treatment (HR 7.22; 95% CI 2.21 to 23.59; p = 0.001), the presence of giant aneurysms (HR 13.59; 95% CI 2.43 to 76.09; p = 0.003), and CAAs that involved bilateral branches of coronary arteries (HR 6.19; 95% CI 1.24 to 30.92; p = 0.026). Among children with giant CAAs, the intervention-free rate was 93.8%, 78.7% and 52.2%, at 1, 5 and 10 years, respectively. Of note, 81% of the small CAAs regressed to a normal size, and for medium CAAs, 50% regressed to normal size. Overall, ~10% of children with CAAs following KD experienced MACE in this cohort. Timely IVIG treatment in children with KD following symptom onset will reduce the risk of MACE. Cautious surveillance to identify cardiac complications should be recommended for children once medium or giant CAAs develop. Trial registration: TCTR20190125004.

Angiographic profile and outcomes in persistent non-valvular atrial fibrillation: A study from tertiary care center in North India

BackgroundThe relationship of atrial fibrillation (AF) with coronary artery disease (CAD) is well established, yet it is often missed. There is evidence of myocardial ischemia on stress imaging in AF patients in the absence of obstructive CAD. In this prospective cohort, we studied the angiographic profiles of non-valvular AF patients. MethodsThe study was a nonrandomized, prospective, single-center observational study of consecutive patients of persistent non-valvular AF. Patients symptomatic for AF despite optimal medical therapy for 3 months were recruited and all underwent coronary angiograms (CAG). Patients with prior history of CAD were excluded. ResultsA total of 70 patients were followed for a mean duration of 12 ± 1.4 months. The mean age of the study group was 66.07 (±11.49) years. Hypertension was the commonest comorbidity seen in 74% patients. Obstructive CAD was present in 32 (46%) patients, non-obstructive (<50% stenosis) CAD in 17 (24%) patients and normal coronaries in 21 (30%) patients. Overall 49 (70%) patients had evidence of CAD. Amongst patients without obstructive CAD, slow flow was seen in 16 (42%) patients. Lower baseline ejection fraction, lower haemoglobin & albumin levels and higher creatinine levels was associated with increased mortality. In patients without obstructive CAD, hospitalizations for fast ventricular rate were significantly increased in those having slow flow on CAG (p = 0.005). ConclusionsMajority (70%) of our patients had evidence of atherosclerotic CAD on CAG. A large proportion of patients without obstructive CAD had slow flow on CAG.

Abstract 14093: Open Thoracic Surgical Implantation of Cardiac Pacemakers in Rodents

Introduction: Cardiovascular science has greatly benefited from bioelectronics and genetic engineering. However, combinations of these approaches have been hampered by challenges in genetic engineering of large animals and implantation of cardiac devices in rodents. New surgical approaches to reliably interface bioelectronics to the heart with minimal disruption to the native physiology are necessary for validation of novel bioelectronics therapies and bioelectronics-enabled in vivo studies of physiology. Objective: To develop an effective and reproducible surgical approach to implant epicardial devices in rodents. Methods: All rat surgeries (n = 138) were performed according to protocols approved by The George Washington University Institutional Animal Care and Use Committee. Inhaled isoflurane vapors provided general anesthesia. After orotracheal intubation, an intercostal incision was made and retracted in order to view the target cardiac implantation area (a). The electrode pad of a novel leadless battery-free pacemaker (b) was sutured or attached by bioadhesive to the epicardium with the device body placed subcutaneously. The ribs, muscle, and skin were subsequently closed. Post-operative care included injectable analgesics. Daily pacing trials confirmed device functionality. Results: Rats survive and quickly recover from the operation without complications. Electrocardiograms reveal that implanted miniature battery-free cardiac pacemakers pace the heart for up to 32 days after surgery (c). Echocardiography and assessment of biomarkers demonstrate no disruption to mechanical function (d) and no evidence of myocardial ischemia (e) or heart failure (f), respectively. Conclusions: This surgical technique reliably implants epicardial devices in rodents. It has broad applications to verify the long-term functionality and biocompatibility of innovative bioelectronics and to conduct in vivo studies of cardiovascular physiology.

Impact of wall shear stress affected by anatomical difference between acute and chronic coronary syndrome in patients with LAD proximal disease

Abstract Recent hemodynamic studies have demonstrated that progression of coronary atherosclerosis occurs at low wall share-stress site, whereas plaque rupture frequently occurs at high share stress site. It is well recognized that wall shear stress is relatively low along the outer walls of the bifurcation. We investigated consecutive 140 patients (77 with acute coronary syndrome (ACS) and 63 with chronic coronary syndrome (CCS) performed PCI for LAD proximal lesions (AHA seg.6) from January 2016 to December 2019. In CCS group, entry criteria included stenosis of at least 90% in the LAD proximal lesion or at least 70% in the LAD proximal lesion and objective evidence of myocardial ischemia (inducible ischemia with either exercise or pharmacologic vasodilator stress or with pressure wire). Exclusion criteria were patients with maintenance dialysis, chronic total occlusion lesions, in-stent restenosis, and clinically diagnosed unstable angina without troponin I elevation. We measured the distance from LMT distal carina to the culprit site (Distance) and plaque location (Location) with intravascular ultrasound and angle between LMT and LAD with cardiovascular angiography analysis system (CAAS) (Angle). The two groups were generally well balanced with regard to baseline clinical characteristics. The mean (±SD) age of the patients was 69.0±11.8 years, and 75% were men. Medication at baseline was also similar between two groups except higher prevalence of statin prescription in CCS group. The Distance was shorter and Angle was steeper in CCS group than in ACS group. The number of patients with Angle less than 150 degrees and with Location in the lateral wall side was much more in CCS group. In this study, plaques in CCS were frequently observed at low shear stress site, whereas those in ACS at high shear stress site. Plaque progression in CCS may be associated with low wall shear stress, and high shear stress may play key role in plaque rupture in ACS. This anatomical difference can partly explain the different mechanisms of onset between of ACS and CCS. Funding Acknowledgement Type of funding sources: None. Anatomical differenceCharacteristics and results

Factors for heterogeneous outcomes of angina and myocardial ischemia without obstructive coronary atherosclerosis

The absence of obstructive coronary artery disease (CAD) in patients with angina is common, but its prognosis is debated. We investigated outcomes of such patients to identify predictors of cardiovascular events. We selected 1014 patients with angina, evidence of myocardial ischemia at the electrocardiogram (ECG) exercise test or imaging stress tests, and nonobstructive CAD (absence of lumen diameter reduction ≥50%) at coronary angiography between 1999 and 2015. Note that, 1905 age- and risk factors-matched asymptomatic subjects served as "real-world" comparators. The primary endpoint was the occurrence of all-cause death or myocardial infarction. At 6-years median follow-up (interquartile range, 3-9 years), the primary endpoint occurred in 53 patients (5.5%, 0.92/100 person-years). Besides similar event rates compared with asymptomatic subjects (hazard ratio [HR] 0.85, 95% confidence interval [CI] 0.62-1.15, p = 0.28), the index population showed a very heterogeneous prognosis. Patients with nonobstructive CAD (HR 1.85, 95% CI 1.02-3.37, p = 0.04, compared with "normal" coronary arteries) and ischemia at imaging tests (HR 2.11, 95% CI 1.07-4.14, p = 0.03, compared with ischemia detected only at the ECG exercise test) were at higher risk and those with both these components showing even >10-fold event rates as compared with the absence of both. Three-hundred and twenty-five patients (34%) continued to experience angina, 69 (7.2%) underwent repeat coronary angiography, and 14 (1.5%) had consequent coronary revascularization for atherosclerosis progression. Apart from the impaired quality of life, angina without obstructive CAD has an overall benign but very heterogeneous prognosis. Nonobstructive CAD and myocardial ischemia at imaging tests both confer a higher risk.

Major adverse events associated with inducible cardiac ischemia during treadmill exercise testing for peripheral artery disease

BackgroundThe coexistence of coronary artery disease and peripheral artery disease (PAD) is well-established. Whether myocardial ischemia by electrocardiography during treadmill testing to evaluate PAD severity is associated with adverse cardiac and limb events has not been established. The aim of the current study is to assess the risk of major adverse cardiac events (MACE), major adverse limb events (MALE), and all-cause mortality in patients with evidence of myocardial ischemia on ECG compared with those without ischemia in patients undergoing treadmill testing for PAD evaluation. MethodsPatients undergoing treadmill exercise ankle-brachial index (ABI) evaluation (January 1, 2003, to December 31, 2006) were identified using the Mayo Clinic Gonda Vascular Laboratory database. Patients with ischemia by electrocardiogram (ECG) were age and sex matched to patients without ischemia. Outcomes were compared by ECG category. ResultsOf 4128 patients who underwent treadmill exercise, 170 (4.1%) had inducible myocardial ischemia by ECG. These were matched with 340 patients without ischemia. The positive ECG group had a higher percentage of diabetes mellitus (31.2% vs 21.8%; P = .02), carotid artery disease (22.4% vs 13.2%; P = .009), exercise-induced angina (14.1% vs 2.9%; P < .0001), and dyspnea (60.6% vs 35.6%; P < .0001). While the resting ABI was similar, the postexercise ABI was lower in the positive ECG group (0.5 vs 0.7; P = .04). After a median follow-up of 8 years, MACE were significantly greater in the positive ECG group (62.4% vs 46.5%; P < .001). MALE were significantly less frequent (17.1% vs 23.2%; P = .02), without an increased risk of amputation. In multivariable analysis, inducible ischemia was associated with higher incidence of MACE (hazard ratio, 1.65; 95% confidence interval, 1.25-2.16; P < .001) and lower incidence of MALE (hazard ratio, 0.51; 95% confidence interval, 0.31-0.84; P < .05). ConclusionsECG monitoring during vascular treadmill testing identified a subset of patients with more frequent MACE but less MALE.

MICROVASCULAR ANGINA IS ASSOCIATED WITH SYSTEMIC DYSFUNCTION OF PERIPHERAL RESISTANCE ARTERIES

Objective: Microvascular angina (MVA) is characterized by functional and structural alterations of resistance coronary arteries without any significant alterations of epicardial coronary arteries. Whether MVA patients present also dysfunction of peripheral resistance arteries is still a matter of debate. We sought to evaluate whether MVA is associated with parameters of systemic microvascular dysfunction. Design and method: Thirteen patients with MVA and 13 healthy control subjects were enrolled in this study. The diagnosis of MVA was based on the presence of typical symptoms of ischemic heart disease, evidence of myocardial ischemia on exercise stress testing and normal epicardial coronary arteries at angiography. Parameters of peripheral microvascualar alterations, arterial stiffness (Pulse Wave Velocity, PWV), and central blood pressure (cBP) and Subendocardial Viability Ratio (SEVR, and index of subendocardial microvascular dysfunction), were evaluated by applanation tonometry. Results: Patients and controls were similar with respect to metabolic parameters, BMI, and renal function. MVA patients were on therapy with beta-blockers (50%), calcium channel blockers (37%), nitrates (12%), renin-angiotensin-blockers (44%), and statins (25%). MVA patients were slightly older than controls (63.6 ± 1.9 vs 53.1 ± 2.0 years, p &lt; 0.05). Albeit in the normal range, peripheral (pSBP) and central (cSBP) systolic BP were significantly higher in MVA patients as compared to controls (pSBP:134.3 ± 2.9 vs 118.5 ± 3.5 mmHg, p &lt; 0.002; and cSBP:124.8 ± 2.9 vs 109.7 ± 2.9 mmHg, p &lt; 0.001). Diastolic BP was similarly preserved in both groups. SEVR, an index of subendocardial microvascular dysfunction, was lower in MVA patients as compared to controls (139.7 ± 4.1 vs 160.4 ± 8.5 %, p &lt; 0.05). Augmentation index (AI), reflected (RPH), and forward (FPH) pulse height, all parameters of peripheral microvascular dysfunction, were also altered in MVA patients as compared to controls (AI:29.0 ± 1.0 vs 19.9 ± 2.4%, p &lt; 0.003; RPH:22.3 ± 1.4 vs 15.3 ± 0.9 mmHg, p &lt; 0.001; FPH:31.0 ± 1.4 vs 24.2 ± 1.4 mmHg p &lt; 0.005). The index of aortic stiffness PWV was similar in both groups (7.20 ± 07 vs 6.6 ± 0.2 m/sec, NS). Conclusions: Patients with MVA on optimal anti-schemic therapy exhibit alterations of parameters of both subendocardial and peripheral microvascular dysfunction, suggesting that coronary microvascular dysfunction is part of a more generalized disorder also involving peripheral resistance arteries.