Detection of traumatic myocardial injury by means of simultaneous T1-201/Tc-99m pyrophosphate tomography--report of three cases

Trauma to the chest can result in cardiac damage, which maybe missed by clinical examination because of associated injuries.Routinely performed non-invasive tests may also be non-diagnostic.Tc-99m pyrophos-phate (PPi) tomography, in this study combinedwith T1-201, is a promising addition to non-invasive evaluation.In three patients with cardiac injury, this technique successfullydetected and localized myocardial necrosis.     

Implementation of monoclonal antibody fluorescence on the Abbott CELL‐DYN Sapphire haematology analyser: evaluation of lymphoid,myeloid and platelet markers

Apart from qualitative flags, that are typically inefficient and uninformative, haematology instruments provide little meaningful information about lymphocyte populations or the lineage of atypical or immature elements, The CELL‐DYN Sapphire haematology analyser uses integrated optical and fluorescence (488 nm) measurements, with FL1 (FITC) and FL2 (PE) detectors being configured for fluorescent analysis. As monoclonal antibodies (Mab) are widely used as cellular probes, and are likely to constitute the future basis for immunodifferentials, we explored the feasibility of implementing immunofluorescence on this routine haematology analyser. An extensive series of Mab (CD2, CD3, CD4, CD8, CD11b, CD13, CD14, CD16, CD19, CD22, CD33, CD34, CD41, CD42b, CD45, CD56, CD61, CD64, CD235a and HLA‐DR) were tested singly or in FITC/PE combinations. Analyser processing and data acquisition was achieved using CD‐Sapphire automated CD61 immunoplatelet or CD3/4/8 assay procedures and, apart from mixing EDTA‐blood and antibody, no further sample manipulation was required. Downloaded raw files were processed with cytometry software, and all evaluated reagents showed population discrimination analogous to flow cytometry. Practical procedures were straightforward and required minimal operator training. Extended information that can be obtained from monoclonal antibodies with a routine haematology analyser has the potential to extend haematology laboratory practices and positively impact laboratory and clinical efficiency.     

Influence of the force--frequency relationship on haemodynamics and left ventricular function in patients with non-failing hearts and in patients with dilated cardiomyopathy

In isolated human myocardium it was shown that a positive force-frequencyrelationship occurs in non-failing myocardium; however, theforce-frequency relationship was found to be inverse in myocardiumfrom failing human hearts. In order to investigate the clinicalrelevance of these experimental findings, the influence of heartrate changes on haemodynamics and left ventricular functionwas studied in eight patients without heart failure and in ninewith failing dilated cardiomyopathy (NYHA II–III). Rightventricular pacing was performed at a rate slightly above sinusrate and at 100, 120 and 140 beats. min^–1 Haemodynamicparameters were obtained by right heart catheterization andby high-fidelity left ventricular pressure measurements. Leftventricular angiography was performed at basal pacing rate andat 100 and 140 beats. min^–1 With increasing heart rate,cardiac index increased in patients with normal left ventricularfunction from 2·9 ± 0·2 to 3·5 ±0·21. min^–1. m^–2 (P<0·01) and decreasedcontinuously in patients with dilated cardiornyopathy from 2·6± 0·1 to 2·2 ± 0·11. min^–1. m^–2 (P<0·05). With increasing heart rate,the maximum rate of left ventricular pressure rise increasedin non-failing hearts from 1388 ± 86 to 1671 ±88 mmHg. s^–1 (P<0·01) and did not change infailing hearts. Ejection fraction decreased from 27 ± 3% to 19 ±2% in patients with dilated cardiomyopathy (P<0·05)when the pacing rate was changed from 84 ± 2 beats. min^–1to 140 beats. min^–1, which was associated with a significantlyincrease in end-systolic volume without significantly changesin end-diastolic volume. In patients with normal left ventricularfunction, when the pacing rate was changed from 85 ±3 beats. min^–1 to 140 beats. min^–1, end-diastolicvolume decreased significantly by 13%, whereas left ventricularend-systolic volume and ejection fraction did not significantlychange. Left ventricular systolic and end-diastolic pressuresdid not significantly change with pacing tachycardia in eithergroup. The frequency-related changes in left ventricular volumesand pressures indicate that the differrent haemodynamic effectsof pacing tachycardia in both groups of patients result predominantlyfrom frequency effects on myocardial function and not from frequencyeffects on preload or afterload. These data indicate that recentexperimental findings of positive force-frequency effects innon-failing and negative force-frequency effects in failinghuman myocardium are relevant for the intact heart.     

Intraindividual Reproducibility of Heart Rate Variability

Heart rate variability was determined from three consecutive Holter recordings performed on days 1, 7, and 28 in 17 normal subjects, in 13 patients with angiographically normal coronary arteries, and in 9 patients with remote myocardial infarctions. Group data of several time and frequency domain measures of heart rate variability were highly reproducible (correlation coefficients 0.629–0.894). However, some individuals exhibited considerably larger day-to-day variations in heart rate variability. Single heart rate indices differed by up to 50% between two Holter recordings. Such potential differences must be considered when repeated heart rate variability determinations are used to assess changes in neurocardiac reflex regulation or effects of therapeutic interventions.     

Washing Machine Associated 50 Hz Detected As Ventricular Fibrillation by An Implanted Cardioverter Defibrillator

SABATÉ, X., et al. : Washing Machine Associated 50 Hz Detected As Ventricular Fibrillation by An Implanted Cardioverter Defibrillator. This case report describes a patient with an automatic ICD who suffered a defibrillation shock without warning symptoms. An electrical interference can be observed in the stored EGM of the episode. The patient explained that the moment he felt the shock he was touching a washing machine. After correct grounding of this machine the patient did not suffer more inappropriate shocks.