Caffeine Consumption and Heart Rate and Blood Pressure Response to Regadenoson

BACKGROUND: Current guidelines recommend that caffeinated products should be avoided for at least 12 hours prior to regadenoson administration. We intended to examine the effect of caffeine consumption and of timing of last dose on hemodynamic effects after regadenoson administration for cardiac stress testing. METHODS: 332 subjects undergoing regadenoson stress testing were enrolled. Baseline characteristics, habits of coffee/caffeine exposure, baseline vital signs and change in heart rate, blood pressure, percent of maximal predicted heart rate, and percent change in heart rate were prospectively collected. RESULTS: Non-coffee drinkers (group 1) (73 subjects) and subjects who last drank coffee >24 hours (group 3) (139 subjects) prior to regadenoson did not demonstrate any difference in systolic blood pressure, heart rate change, maximal predicted heart rate and percent change in heart rate. Systolic blood pressure change (15.2±17.1 vs. 7.2±10.2 mmHg, p = 0.001), heart rate change (32.2±14 vs. 27.3±9.6 bpm, p = 0.038) and maximal predicted heart rate (65.5±15.6 vs. 60.7±8.6%, p = 0.038) were significantly higher in non-coffee drinkers (group 1) compared to those who drank coffee 12-24 hours prior (group 2) (108 subjects). Subjects who drank coffee >24 hours prior (group 3) exhibited higher systolic blood pressure change (13±15.8 vs. 7±10.2, p = 0.007), and heart rate change (32.1±15.3 vs. 27.3±9.6, p = 0.017) as compared to those who drank coffee 12-24 hours prior to testing (group 2). CONCLUSIONS: Caffeine exposure 12-24 hours prior to regadenoson administration attenuates the vasoactive effects of regadenoson, as evidenced by a blunted rise in heart rate and systolic blood pressure. These results suggest that caffeine exposure within 24 hours may reduce the effects of regadenoson administered for vasodilatory cardiac stress testing

Coronavirus Disease-2019 in Heart Transplant Recipients in Southeastern Michigan: A Case Series

BACKGROUND: Since coronavirus disease 2019 (COVID-19) was first identified in Wuhan, China, in December 2019, the number of cases has risen exponentially. Clinical characteristics and outcomes among patients with orthotopic heart transplant (OHT) with COVID-19 remain poorly described. METHODS: We performed a retrospective case series of patients with OHT with COVID-19 admitted to 1 of 2 hospitals in Southeastern Michigan between March 21 and April 22, 2020. Clinical data were obtained through review of the electronic medical record. Final date of follow-up was May 7, 2020. Demographic, clinical, laboratory, radiologic, treatment, and mortality data were collected and analyzed. RESULTS: We identified 13 patients with OHT admitted with COVID-19. The mean age of patients was 61 ± 12 years, 100% were black males, and symptoms began 6 ± 4 days before admission. The most common symptoms included subjective fever (92%), shortness of breath (85%), and cough (77%). Six patients (46%) required admission to the intensive care unit. Two patients (15%) died during hospitalization. CONCLUSIONS: Black men may be at increased risk for COVID-19 among patients with OHT. Presenting signs and symptoms in this cohort are similar to those in the general population. Elevated inflammatory markers on presentation appear to be associated with more severe illness

Factor XIII Val34Leu polymorphism and recurrent myocardial infarction in patients with coronary artery disease

Factor XIII (FXIII) is necessary for cross linking of fibrin strands and generation of stable fibrin clot. FXIII Val34Leu is a common genetic single nucleotide polymorphism that has been associated with accelerated fibrin stabilization and reduced rate of fibrinolysis. The contribution of Val34Leu to long term risk of recurrent myocardial infarction (MI) in patients with coronary stenting has not been conclusively established. The objective of the study was to examine the effects of Val34Leu on fibrin generation, platelet aggregation, and long term clinical outcomes in patients with coronary artery disease treated with dual antiplatelet therapy. Patients with angiographically documented coronary artery disease who were treated with aspirin and clopidogrel were enrolled (n = 211). Light transmittance aggregometry and plasma fibrin clot formation using thrombelastography (TEG) were determined. Genotyping of Val34Leu was performed using Taqman assay. Clinical events during follow up were recorded. Homozygous carriers of 34Leu variant had significantly shorter fibrin clot formation time as compared to wild type individuals (TEG K: 1.27 ± 0.3 vs. 1.68 ± 1.1 min, p = 0.011). The Val34Leu variant was associated with gene dose dependent increased risk of MI (log rank, p = 0.002) or occurrence of composite of MI and CV death (log rank, p = 0.005) with highest event rates observed in homozygous carriers of 34Leu. In summary, FXIII Val34Leu polymorphism was associated with increased rate of fibrin stabilization in homozygous carriers of the variant and may increase risk of recurrent MI and death in patients with angiographically established coronary artery disease treated with dual antiplatelet therapy

Typhoid ulcer causing life-threatening bleeding from Dieulafoy's lesion of the ileum in a seven-year-old child: a case report

<p>Abstract</p> <p>Introduction</p> <p>We describe a case of rare complication of typhoid fever in a seven-year-old child and review the literature with regard to other rare causes of bleeding per rectum. Dieulafoy's lesion is an uncommon but important cause of recurrent gastrointestinal bleeding. Dieulafoy's lesion located extragastrically is rare. We report a case of typhoid ulcer with Dieulafoy's lesion of the ileum causing severe life-threatening bleeding and discuss the management of this extremely uncommon entity.</p> <p>Case presentation</p> <p>As a complication of typhoid fever, a seven-year-old Kurdish girl from Northern Iraq developed massive fresh bleeding per rectum. During colonoscopy and laparotomy, she was discovered to have multiple bleeding ulcers within the Dieulafoy's lesion in the terminal ileum and ileocecal region.</p> <p>Conclusion</p> <p>Although there is no practical way of predicting the occurrence of such rare complications, we emphasize in this case report the wide array of pathologies that can result from typhoid fever.</p

Absorbed dose to water determination for kilo-voltage X-rays using alanine/EPR dosimetry systems

International audienceAlanine's relative response to kilo-voltage X-rays, compared to 60 Co reference quality beam, was studied in this work, in order to determine correction factors to be applied to alanine's response when irradiated with low to medium energy X-rays (up to 300 keV). The relative response to kilo-voltage X-rays of Aerial's alanine dosimeters was determined by three distinct methods: experimental measurements using alanine dosimeters and a calibrated PTW Farmer 30013 ion chamber, Monte Carlo simulations using MCNPX code and finally, analytical calculations based on weighting of X-ray spectra by NIST's published mass energy absorption coefficients. Two sets of X-ray beam qualities, covering high voltages ranging from 50 kV up to 280 kV, were used to study the energy dependence of the alanine dosimeter's response. Obtained results were consistent within 2.1% (average standard deviation at k = 1)

Testing Performances of a Special AC Induction Motor Used in Electric Car

AbstractIN this practical research a laboratory testing desk was build with fully functional system including 3-Phase Induction Motor, AC Controller and Battery Bank with charger, enabling the practically verification of performances and behaviour of the complete electric drive system containing the exact parts that would be proposed to use in converting a diesel or petrol powered vehicle to an electric car. The tests were carried on a 3-Phase IM with special design and construction suitable to be used in electric car. The resistive loads of the car were simulated using a synchronous generator with a variable electric resistive load coupled to 3-Phase IM. An electronic car foot pedal and a battery bank were used as main source of power with a capacity suitable for the size of a light weight or medium size car.The performances of 3-Phase IM were tested in several practical cases simulating the running of 3-Phase IM on no load, running of 3-Phase IM to accelerate the car from stop position to reach a certain speed fixed by driver, for different resistive loads of the car. Running of 3-Phase IM to accelerate the car from stop position to reach a certain speed fixed by driver, keeping this speed for a certain period of time and decelerate, with different resistive loads of the car. Variations of rotation speed in time and variation of active torque in time of 3-Phase IM were studied for these cases, when different resistive load coupled to 3-Phase IM. Some conclusions and remarks about practical performances and behaviour of IM were given

Poor agreement between pulmonary capillary wedge pressure and left ventricular end-diastolic pressure in a veteran population.

BACKGROUND: Accurate determination of left ventricular filling pressure is essential for differentiation of pre-capillary pulmonary hypertension (PH) from pulmonary venous hypertension (PVH). Previous data suggest only a poor correlation between left ventricular end-diastolic pressure (LVEDP) and its commonly used surrogate, the pulmonary capillary wedge pressure (PCWP). However, no data exist on the diagnostic accuracy of PCWP in veterans. Furthermore, the effects of age and comorbidities on the PCWP-LVEDP relationship remain unknown. METHODS: We investigated the PCWP-LVEDP relationship in 101 patients undergoing simultaneous right and left heart catherization at a large VA hospital. PCWP performance was evaluated using correlation and Bland-Altman analyses. Area under Receiver Operating Characteristics curves (AUROC) for PCWP were determined. RESULTS: PCWP-LVEDP correlation was moderate (r = 0.57). PCWP-LVEDP calibration was poor (Bland-Altman limits of agreement -17.2 to 11.4 mmHg; mean bias -2.87 mmHg). 59 patients (58.4%) had pulmonary hypertension; 15 (25.4%) of those met pre-capillary PH criteria based on PCWP. However, if LVEDP was used instead of PCWP, 7/15 patients (46.6%) met criteria for PVH rather than pre-capillary PH. When restricting analysis to patients with a mean pulmonary artery pressure of ≥25 mmHg and pulmonary vascular resistance of >3 Wood units (n = 22), 10 patients (45.4%) were classified as pre-capillary PH based on PCWP ≤15 mmHg. However, if LVEDP was used, 4/10 patients (40%) were reclassified as PVH. Among patients with any type of pulmonary hypertension, PCWP discriminated moderately between high and normal LVEDP (AUROC, 0.81; 95%CI 0.69-0.94). PCWP-LVEDP correlation was particularly poor in patients with COPD or obesity. CONCLUSION: Reliance on PCWP rather than LVEDP results in misclassification of veterans as having pre-capillary PH rather than PVH in almost 50% of cases. This is clinically relevant, as misclassification may lead to inappropriate therapies and adverse events

Patient Characteristics.

<p>Angiotensin-converting enzyme inhibitor. ARB: Angiotensin receptor blocker</p><p>¹ Comparison between non-coffee drinker (group 1) and subject who drank coffee 12–24 hours prior (group 2)</p><p>² Comparison between non-coffee drinker (group 1) and subjects who drank coffee more than 24 hours prior (group 3)</p><p>³ Comparison between subjects who drank coffee 12–24 hours (group 2) and subjects who drank coffee more than 24 hours prior (group 3)</p><p>⁴ Comparison between group 1, 2 and 3</p><p>Patient Characteristics.</p

Coffee Consumption Among Group With 12–24 Hour Hold.

<p>HR: heart rate. SBP: systolic blood pressure. MPHR: maximal predicted heart rate. % ChangeHR: percent change in heart rate</p><p>¹Comparison among group 2 (12–24 hour caffeine hold) based on number of coffee drink consumed</p><p>Coffee Consumption Among Group With 12–24 Hour Hold.</p