First Author: Wei Kong
All Authors: Kong W, Huang J, Rollins DL, Ideker RE, Smith WM
Journal Title: Physiological measurement
Abstract: We have developed an eight-channel telemetry system for studying experimental models of chronic cardiovascular disease. The system is an extension of a previous device that has been miniaturized, reduced in power consumption and provided with increased functionality. We added sensors for ventricular dimension, and coronary artery blood flow and arterial blood pressure that are suitable for use with the system. The telemetry system consists of a front end, a backpack and a host PC. The front end is a watertight stainless steel case with all sensor electronics sealed inside; it acquires dimension, flow, pressure and five cardiac electrograms from selected locations on the heart. The backpack includes a control unit, Bluetooth radio, and batteries. The control unit digitizes eight channels of data from the front end and forwards them to the host PC via Bluetooth link. The host PC has a receiving Bluetooth radio and Labview programs to store and display data. The whole system was successfully tested on the bench and in an animal model. This telemetry system will greatly enhance the ability to study events leading to spontaneous sudden cardiac arrest.
Better Clinical Outcome For Rehospitalization Heart Failure Patients With Reduced Left Ventricular Function in Mode of Sudden Cardiac Death
I'm Not Sure We Had A Choice?: Decision Quality and The Use of Cardiac Implantable Electronic Devices In Older Adults With Cognitive Impairment
Authors: Kratz A, Lewandrowski KB, Siegel AJ, Chun KY, Flood JG, Van Cott EM, Lee-Lewandrowski E
Abstract: Participants in marathon races may require medical attention and the performance of laboratory assays. We report the changes in basic biochemical parameters, cardiac markers, CBC counts, and WBC differentials observed in participants in a marathon before, within 4 hours, and 24 hours after a race. The concentrations of glucose, total protein, albumin, uric acid, calcium, phosphorus, serum urea nitrogen, creatinine, bilirubin, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, total creatine kinase, creatine kinase-MB, myoglobin, and the anion gap were increased after the race, consistent with the effects of exertional rhabdomyolysis and hemolysis. The increase in WBC counts was due mainly to neutrophilia and monocytosis, with a relative decrease in circulating lymphocytes, consistent with an inflammatory reaction to tissue injury. A significant percentage of laboratory results were outside the standard reference ranges, indicating that modified reference ranges derivedfrom marathon runners might be more appropriatefor this population. We provide a table of modified reference ranges (or expected ranges) for basic biochemical, cardiac, and hematologic laboratory parameters for marathon runners.
Authors: Dixon B, Campbell DJ, Santamaria JD
Abstract: Inflammation has been shown to trigger microvascular thrombosis. Patients undergoing cardiac surgery sustain significant inflammatory insults to the lungs and in addition are routinely given anti-fibrinolytic agents to promote thrombosis. In view of these risk factors we investigated if evidence of pulmonary microvascular thrombosis occurs following cardiac surgery and, if so, whether a pre-operative heparin infusion may limit this.Double-blind randomised controlled trial.Tertiary university affiliated hospital.Twenty patients undergoing elective cardiac surgery.Patients were randomised to receive a pre-operative heparin infusion or placebo. All patients were administered aprotinin.Pulmonary microvascular obstruction was estimated by measuring the alveolar dead-space fraction. Pulmonary coagulation activation was estimated by measuring the ratio of prothrombin fragment levels in radial and pulmonary arterial blood. Systemic tissue plasminogen activator (t-PA) levels were also assessed. In the placebo group cardiac surgery triggered increased alveolar dead-space fraction levels and the onset of prothrombin fragment production in the pulmonary circulation. Administration of pre-operative heparin was associated with a lower alveolar dead-space fraction (p < 0.05) and reduced prothrombin fragment production in the pulmonary circulation (p < 0.05). Pre-operative heparin also increased baseline t-PA levels (p < 0.05).The changes in the alveolar dead-space fraction and pulmonary coagulation activation suggest that pulmonary microvascular thrombosis develops during cardiac surgery and this may be limited by a pre-operative heparin infusion.
Authors: Hedman K, Tamás É, Bjarnegård N, Brudin L, Nylander E
Abstract: Most studies on cardiac function in athletes describe overall heart function in predominately male participants. We aimed to compare segmental, regional and overall myocardial function and synchrony in female endurance athletes (ATH) and in age-matched sedentary females (CON).In 46 ATH and 48 CON, echocardiography was used to measure peak longitudinal systolic strain and myocardial velocities in 12 left ventricular (LV) and 2 right ventricular (RV) segments. Regional and overall systolic function were calculated together with four indices of dyssynchrony.There were no differences in regional or overall LV systolic function between groups, or in any of the four dyssynchrony indices. Peak systolic velocity (s') was higher in the RV of ATH than in CON (9.7±1.5 vs 8.7±1.5?cm/s, p=0.004), but not after indexing by cardiac length (p=0.331). Strain was similar in ATH and CON in 8 of 12 LV myocardial segments. In septum and anteroseptum, basal and mid-ventricular s' was 6-7% and 17-19% higher in ATH than in CON (p<0.05), respectively, while s' was 12% higher in CON in the basal LV lateral wall (p=0.013). After indexing by cardiac length, s' was only higher in ATH in the mid-ventricular septum (p=0.041).We found differences between trained and untrained females in segmental systolic myocardial function, but not in global measures of systolic function, including cardiac synchrony. These findings give new insights into cardiac adaptation to endurance training and could also be of use for sports cardiologists evaluating female athletes.
Authors: Powell MD, Burke MS, Dahle D
Abstract: Phenylhydrazine injections (0.3 mg kg(-1) , followed by a second injection of 0.1 mg kg(-1) 7 days later) induced a reproducible and stable anaemia in Atlantic halibut Hippoglossus hippoglossus, reducing the haematocrit and haemoglobin by 70.0 and 75.5%, respectively, over 3 weeks. There were no changes in blood electrolyte or lactate concentrations, although anaemic fish showed a 37.5 and 33.0% increase in cardiac somatic index and ventricular somatic index, respectively, compared with dimethyl sulphur oxide (DMSO) and saline vehicle controls. Changes in cardiac somatic indices did not correlate with the ratio of ventricular length:height and length:width did correlate with haematocrit and haemoglobin indicating that changes in cardiac shape may occur as a function of anaemic hypoxemia.
Authors: Trouillet JL, Combes A, Vaissier E, Luyt CE, Ouattara A, Pavie A, Chastre J
Abstract: Prolonged mechanical ventilation after cardiac surgery is a serious complication that warrants search for new treatment strategies. Our objective was to identify patients still requiring mechanical ventilation 3 days after the operation and those successfully weaned by day 10 to avoid needless and potentially hazardous interventions, such as tracheostomy.All consecutive patients still mechanically ventilated on day 3 after cardiac surgery were included in a prospective observational cohort. Patients' preoperative, intraoperative, and postoperative data were recorded. Logistic regression analysis was used to identify factors associated with successful weaning from mechanical ventilation by postoperative day 10.Among 2620 patients who underwent cardiac surgery, 163 were still receiving ventilatory assistance on day 3. By day 10, 50 (31%) patients had been successfully weaned, 78 (48%) were still receiving mechanical ventilation, and 35 (21%) had died. Multivariable regression analysis retained 6 day-3 factors associated with successful weaning (odds ratio): urine output 500 mL/24 hours or greater (16.47), Glasgow coma score of 15 (9.75), arterial bicarbonates 20 mmol/L or greater (6.09), platelet count 100 g/L or greater (3.18), patients without inotropic support with epinephrine/norepinephrine (2.84), and absence of lung injury (2.40). The area under the receiver operating characteristics curve for the simple score based on this model's beta-coefficients was 0.84 (95% confidence intervals, 0.78-0.91). Depending on the threshold chosen for this scoring system, only 3% to 17% of the patients would have received a needless intervention.A simple score based on postoperative day-3 physiologic parameters might help intensivists early identify patients with a strong likelihood of success in rapid weaning from mechanical ventilation and therefore prevent needless procedures aimed at reducing duration of mechanical ventilation and related complications.
Authors: Chapman J, Bock A, Dussol B, Fritsche L, Kliem V, Lebranchu Y, Oppenheimer F, Pohanka E, Salvadori M, Tufveson G
Abstract: Kidneys obtained from donors after cardiac death (DCD) are known to have higher rates of primary nonfunction and delayed graft function (DGF) than heart beating cadaveric donor (CAD) kidneys, but little is known about long-term function of DCD grafts that survive to 1 year. To investigate the outcomes of renal transplant recipients whose DCD graft functioned for at least 1 year, this study analyzed data collected from 326 DCD graft recipients and 340 CAD-matched controls enrolled in a prospective, multinational, observational study--Neoral-MOST (Multinational Observational Study in Transplantation) (Novartis, Basel, Switzerland). No differences were found in the demographics or immunosuppression between the two groups. All patients received a Neoral-based immunosuppressive regimen. Donors after cardiac death graft recipients had a higher incidence of DGF (40% vs. 27% CAD; P < 0.001). One year glomerular filtration rate (GFR) and GFR-decline after 1 year were similar in DCD and CAD recipients (GFR 56 ml/min DCD vs. 59 ml/min CAD; GFR-decline -1.3 ml/min DCD vs. -1.4 ml/min CAD; P = not significant). Multifactorial analyses confirmed that GFR at 1 year was significantly influenced by donor age and gender, DGF, and acute rejection; however, DCD status was not an independent risk factor in cyclosporine-treated patients with grafts that had functioned for at least 1 year.
Authors: Siegel AJ
Abstract: While endurance exercise such as marathon training is cardioprotective, an increasing frequency of race-related cardiac arrests and sudden death has been observed in middle-aged men since the year 2000. An evidence-based strategy for prevention is considered based on identifying atherothrombosis as the underlying cause in this susceptible subgroup. Review of all articles on PubMed related to acute cardiac events during marathons. Male gender and the marathon compared with the half-marathon were identified as significant risk factors for race-related cardiac arrests, which events increased 2.3-fold in the latter half of a 10-year prospective registry beginning in the year 2000. There were 50 cardiac arrests in runners who were 86% male with a mean age of 42?years. The main cause of sudden death was atherosclerotic heart disease in those over the age of 40 including myocardial infarction in 12 of 13 (93%) cases over the age of 45 as assessed retrospectively. Inflammatory biomarkers predicting acute cardiac events and hypercoagulability with in vivo platelet activation were demonstrated in same-aged asymptomatic middle-aged men during marathons. Excess cardiac morbidity and mortality in middle-aged men during marathons is mediated by atherothrombosis which may render non-obstructive coronary atherosclerotic plaques vulnerable to rupture. Prerace low-dose aspirin usage is prudent to protect susceptible runners from a high, if transient, risk for cardiac arrest during races as evidence-based to prevent first myocardial infarctions in same-aged healthy men.
Authors: Serpytis P, Navickas P, Navickas A, Serpytis R, Navickas G, Glaveckaite S
Abstract: The overall evidence base regarding delirium has been growing steadily over the past few decades. There has been considerable analysis of delirium concerning, for example, mechanically ventilated patients, patients in the general intensive care unit (ICU) setting, and patients with exclusively postoperative delirium. Nevertheless, there are few studies regarding delirium in a cardiovascular ICU (ICCU) setting and especially scarce literature about the particular features of delirium relating to patient age and gender.We aimed to determine particular features of delirium not induced by alcohol or other psychoactive substances, relating to patient age and gender in an ICCU setting.An observational cross-sectional study was conducted to evaluate patients with delirium in a Lithuanian ICCU. From a sample of 19,007 ICCU admissions, 337 (1.8%) had documented delirium diagnosed through liaison and consultation with a psychiatrist and were included in the final analysis. The obtained data was then evaluated and analysed according to patients' gender and four categorised age groups: < 65 years, 65-74 years, 75-84 years, and ? 85 years.Female patients who experienced delirium demonstrated a higher prevalence of hypertension, hyponatraemia, heart failure, cardiac rhythm and conduction disorders, myocardial infarction (MI), and dementia. The men, who were on average seven years younger than the women, significantly more often had hypokalaemia, double- or triple-vessel coronary artery disease, and sepsis. Furthermore, MI, ST-segment elevated MI, and Killip class 4 were most frequent amongst patients less than 65 years of age. Moreover, the youngest patient group demonstrated the highest mortality.Our investigation presented a number of associated peculiarities related to gender and age. It was shown that delirium is a severe complication that more often affects men amongst patients < 65 years old and more frequently affects women in the age group of ? 85 years. Male patients < 65 years old, who develop delirium should be treated with more caution because they tend to have more serious forms of disorder and a poorer prognosis.
Authors: Hashimura H, Ishibashi-Ueda H, Yonemoto Y, Ohta-Ogo K, Matsuyama TA, Ikeda Y, Morita Y, Yamada N, Yasui H, Naito H
Abstract: Gadolinium contrast agents used for late gadolinium enhancement (LGE) distribute in the extracellular space. Global diffuse myocardial LGE pronounced in the subendocardial layers is common in cardiac amyloidosis. However, the pathophysiological basis of these findings has not been sufficiently explained. A 64-year-old man was admitted to our hospital with leg edema and nocturnal dyspnea. Bence Jones protein was positive in the urine, and an endomyocardial and skin biopsy showed light-chain (AL) amyloidosis. He died of ventricular fibrillation 3 months later. 9 days before death, the patient was examined by cardiac magnetic resonance (CMR) imaging on a 3-T system. We acquired LGE data at 2, 5, 10, and 20 min after the injection of gadolinium contrast agents, with a fixed inversion time of 350 ms. Myocardial LGE developed sequentially. The myocardium was diffusely enhanced at 2 min, except for the subendocardium, but LGE had extended to almost the entire left ventricle at 5 min and predominantly localized to the subendocardial region at 10 and 20 min. An autopsy revealed massive and diffused amyloid deposits in perimyocytes throughout the myocardium. Old and recent ischemic findings, such as replacement fibrosis and coagulative myocyte necrosis, were evident in the subendocardium. In the intramural coronary arteries, mild amyloid deposits were present within the subepicardial to the mid layer of the left ventricle, but no stenotic lesions were evident. However, capillaries were obstructed by amyloid deposits in the subendocardium. In conclusion, the late phase of dynamic LGE (at 10 and 20 min) visualized in the subendocardium corresponded to the interstitial amyloid deposition and subendocardial fibrosis caused by ischemia in our patient.
Authors: Paik UH, Lee TR, Kang MJ, Shin TG, Sim MS, Jo IJ, Song KJ, Jeong YK
Abstract: Therapeutic hypothermia has become the standard treatment for unconscious patients in cardiac arrest. Although various body parts, including the oesophagus, rectum, bladder and tympanum, can be used for measurement of the core temperature, the oesophageal temperature is preferred because of its accuracy and stability. We first investigated the success rate and procedure time of oesophageal temperature probe (ETP) insertion according to the insertion method.The conventional method involved blind insertion through nasal orifices. The alternative method was insertion with Magill's forceps or long forceps under visualisation using a direct laryngoscope. The new method was performed as follows: (1) insertion of another endotracheal tube (ETT) orally into the oesophagus; (2) insertion of a temperature probe into the hole of the ETT; (3) removal of the ETT. To compare the success rates and procedure times according to the insertion method, we collected data retrospectively from the prospective Samsung Medical Centre hypothermia database and medical records.A total of 91 cases were examined. Insertion was performed using the conventional method in 36 cases, the alternative method in 26, and the new method in 29. Rates of success on the first attempt were 63.9%, 65.4% and 100%, and procedure times were 33.2 ± 13.6, 33.3 ± 17.8 and 27.0 ± 7.9 min, for the conventional, alternative and new methods, respectively. The initial success rates and procedure times were significantly different among the three groups (p<0.01).The new ETP insertion method had a better first attempt success rate than the conventional method and the alternative method.