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Background: Increased pre-hospital delay during acute coronary syndrome (ACS) events contributes to worse outcome., Objectives: The purpose of this study was to assess the effectiveness of an implanted cardiac monitor with real-time alarms for abnormal ST-segment shifts to reduce pre-hospital delay during ACS events., Methods: In the ALERTS (AngeLmed Early Recognition and Treatment of STEMI) pivotal study, subjects at high risk for recurrent ACS events (n = 907) were randomized to control (Alarms OFF) or treatment groups for 6 months, after which alarms were activated in all subjects (Alarms ON). Emergency department (ED) visits with standard-of-care cardiac test results were independently adjudicated as true- or false-positive ACS events. Alarm-to-door (A2D) and symptom-to-door (S2D) times were calculated for true-positive ACS ED visits triggered by 3 possible prompts: alarm only, alarms + symptoms, or symptoms only., Results: The Alarms ON group showed reduced delays, with 55% (95% confidence interval [CI]: 46% to 63%) of ED visits for ACS events <2 h compared with 10% (95% CI: 2% to 27%) in the Alarms OFF group (p < 0.0001). Results were similar when restricted to myocardial infarction (MI) events. Median pre-hospital delay for MI was 12.7 h for Alarms OFF and 1.6 h in Alarms ON subjects (p < 0.0089). Median A2D delay was 1.4 h for asymptomatic MI. Median S2D delay for symptoms-only MI (no alarm) in Alarms ON was 4.3 h., Conclusions: Intracardiac monitoring with real-time alarms for ST-segment shift that exceeds a subject's self-normative ischemia threshold level significantly reduced the proportion of pre-hospital delays >2 h for ACS events, including asymptomatic MI, compared with symptoms-only ED visits in Alarms OFF. (AngeLmed for Early Recognition and Treatment of STEMI [ALERTS]; NCT00781118)., (Copyright © 2019. Published by Elsevier Inc.)

Objectives: The purpose of this study was to evaluate the hypothesis that the increase in lumen area induced by percutaneous transluminal coronary angioplasty is secondary to a change in lesion (segmental) distensibility., Background: Despite the widespread use of coronary angioplasty, the precise mechanism (or mechanisms) of lumen area improvement remains poorly understood., Methods: Quantitative coronary angiography was used to measure the minimal (contrast agent filled) balloon diameters at 1 to 5 atm, inclusive, during the first and final balloon inflations in 24 lesions successfully treated with coronary angioplasty. To rule out possible confounding effects due to changes in balloon material distensibility during repeated inflations, five control balloons were studied ex vivo. In parallel, intravascular ultrasound imaging was utilized to compare the segmental distensibility (change in lumen area during the cardiac cycle) of eight disease-free and seven mildly diseased coronary segments and seven segments after successful balloon angioplasty., Results: Minimal balloon diameters increased significantly between the first and final inflations (46%, 33%, 26%, 14% and 10% at 1, 2, 3, 4 and 5 atm, respectively, all p < 0.0001), demonstrating an increase in arterial distensibility after successful coronary angioplasty. No significant changes in balloon diameters were observed during sequential initial inflations at 1 and 2 atm (n = 5). Minimal increases in balloon diameters were observed during repeated balloon inflations in the ex vivo studies (4.9 +/- 1% [mean +/- SEM]). A distensibility index, derived from the intravascular ultrasound data, was not different between the balloon-dilated and the normal segments but was significantly lower in mildly diseased sites (14.7 +/- 2.2 vs. 12.9 +/- 1.2 vs. 6.9 +/- 1.9, respectively, p < 0.05) despite a smaller plaque area (7.3 +/- 1 vs. 11.3 +/- 1 mm2, proximal/nondilated vs. dilated segments, respectively, p < 0.05)., Conclusions: Coronary distensibility is significantly impaired in atherosclerotically diseased coronary segments and increases significantly after balloon angioplasty. This increase in segmental coronary compliance after coronary angioplasty may create a larger lumen area by allowing the vessel to distend in response to normal intraarterial pressure.

Objectives: The purpose of this study was to determine whether dietary fish oil supplementation enhances endothelium-mediated vasodilator responses in human heart transplant recipients, a group known to have coronary artery disease and endothelial dysfunction., Background: Omega-3 fatty acid supplementation has been shown to enhance endothelium-dependent coronary vasodilation in animal models of atherosclerosis., Methods: Endothelium-dependent vasodilator responses to intracoronary acetylcholine infusion and endothelium-independent responses to nitroglycerin were evaluated in heart transplant recipients who received a high dose of dietary supplementation with omega-3 fatty acids for 3 weeks (5 g of eicosapentaenoic acid plus docosahexaenoic acid/day, n = 7) and compared with responses in a group of matched heart transplant recipients who did not receive fish oil (control patients, n = 7). Acetylcholine was selectively infused into the midportion of the left anterior descending or left circumflex coronary artery, with the noninfused left coronary artery serving as a control vessel. Serial coronary angiograms were performed after infusion with increasing doses of acetylcholine (infused concentrations 10(-6) to 10(-3) mol/liter) and after intracoronary nitroglycerin administration., Results: The patients treated with fish oil showed a normal vasodilator response to acetylcholine with 14 +/- 2.5% and 15 +/- 7% vasodilation (vs. baseline diameter) at infused acetylcholine concentrations of 10(-5) and 10(-4) mol/liter, respectively. In contrast, the control patients demonstrated vasoconstrictor responses (-1 +/- 1% and -9 +/- 4%) to acetylcholine at these same doses (p < 0.05 and < 0.005, respectively, for treated vs. control patients). There were no differences in the response to nitroglycerin between the control and treated patients., Conclusions: Dietary supplementation with fish oil significantly alters endothelium-dependent coronary vasodilation in heart transplant recipients without alteration of the responses to endothelium-independent vasodilation. Whether this enhancement of endothelial function can beneficially alter the natural history of heart transplant atherosclerosis warrants further study.

Objectives: This study was designed to describe the clinical effects of ultrasound energy on guide-wire-induced arterial vasoconstriction., Background: We have previously shown that ultrasound energy (20 kHz) delivered by a wire probe produces dose-dependent, endothelium-independent smooth muscle relaxation capable of reversing both receptor-mediated and voltage-dependent vasoconstriction in vitro., Methods: A high intensity, low frequency ultrasound catheter system was used to recanalize total occlusions in the superficial femoral arteries of two patients. After recanalization, the proximal residual stenoses were each less than 15%. However, distal arterial vasospasm was found angiographically in a popliteal artery of one patient and in an anterior tibial artery of another. Subsequently, the ultrasound catheter probe was advanced to the sites of arterial vasospasm (diffuse in one, focal in one)., Results: After 30 and 90 s, respectively, of exposure to ultrasound energy with a frequency of 19.5 kHz, peak tip amplitude of 111 microns and power output at the transducer of 25 W, the vasospasm resolved in each arterial segment., Conclusions: Our findings are the first reported clinical cases documenting that catheter-delivered low frequency, high intensity ultrasound induces arterial vasodilation at the site of vasoconstriction. These biologic effects appear to be relatively unique for an angioplasty device and may have potential clinical importance.

The long-term efficacy of surgical correction of Wolff-Parkinson-White syndrome was evaluated in 45 consecutive patients. Before surgery, 42 patients had reciprocating tachycardia and 12 had atrial fibrillation. The principal operative procedure was endocardial incision in 42 patients, endocardial cryoablation in 2 patients and epicardial cryoablation without dissection of the atrioventricular (AV) fat pad in 1 patient. Two patients had perioperative complications. One patient had bleeding that necessitated reoperation, and one had a right cerebral stroke with subsequent clearing of neurologic deficit. At postoperative electrophysiologic study, only the patient who underwent epicardial cryoablation had conduction over an accessory connection. Two others had intermittent delta waves in the early postoperative period but no accessory connection conduction at electrophysiologic study. During a mean follow-up of 3.1 years, the patient with ineffective cryoablation had recurrent orthodromic tachycardia, and one other patient had late recurrence of delta waves without arrhythmias. Four other patients had frequent palpitation, which was caused by premature ventricular complexes in three and sinus tachycardia in one. Seventeen patients had occasional "skipped beats" without recurrence of tachyarrhythmias. Twelve of 13 patients whose arrhythmias limited employment before surgery returned to work after surgery. By actuarial analysis at 1, 2 and 3 years, all patients were alive and 98% were free from tachyarrhythmias. Surgical correction of Wolff-Parkinson-White syndrome provides excellent long-term results with low morbidity. Patients who are disabled by arrhythmias return to work after successful surgery. Delta waves may persist or recur without return of arrhythmias. Minor postoperative episodes of palpitation are common and do not correlate with tachyarrhythmias.