Mechanical correlates of the third heart sound

AbstractIn seven chronically instrumented conscious dogs, micromanometers measured left ventricular pressure, and ultrasonic dimension transducers measured left ventricular minor-axis diameter; the latter recording was filtered to examine data between 20 and 100 Hz. Acceptable external heart sounds were recorded with a phonocardiographic microphone in four of the seven dogs. With each dog sedatede, intubated and mechanically ventilated, data were obtained during hemodynamic alterations produced by volume loading, phenylephrine, calcium infusion and vena caval occlusion.Damped oscillations were noted consistently in the left ventricular diameter waveform toward the end of rapid ventricular filling. These wall vibrations, assessed by the Altered diameter, correlated well with the third heart sound (S3) on the phonocardiogram. The peak frequency of the wall vibrations increased with increased diastolic pressure (p = 0.004), probably reflecting an increase in myocardlal wall stiffness. In contrast, the amplitude of the vibrations varid directly with left ventricular filling rate (p = 0.0001).Thus, S3seemed to be related specifically to ventricular wall vibrations during rapid filling, and the spectra of the amplitude-frequency relation shifted toward the audible range with increases in diastolic pressure, wall stiffness or filling rate. Spectral analysis of S3may be useful in assessing pathologic chances in myocardial wall properties

Twenty-five-year outcomes after multiple internal thoracic artery bypass

ObjectiveCoronary artery bypass grafting with multiple internal thoracic artery grafts is currently controversial. This study assessed single institutional outcomes with multiple internal thoracic artery grafting for guidance with future clinical decisions.MethodsIn 19,482 patients undergoing multivessel coronary artery bypass grafting (1984-2009), baseline characteristics were recorded in a prospective databank, and follow-up was obtained by questionnaires, phone contact, or National Death Index. Outcomes examined were subsequent myocardial infarction, percutaneous coronary intervention, reoperative coronary artery bypass grafting, all-cause death, and a composite of the 4. Three groups were defined: (1) no internal thoracic artery graft (1874/19,482 or 9%); (2) single internal thoracic artery grafts and adjunctive venous conduits (single internal thoracic artery; 16,881/19,482 or 87%); and (3) multiple internal thoracic artery grafts (728/19,482 or 4%). Multivariable Cox modeling adjusted for differences in baseline characteristics, and comparisons were performed using area under the curve analysis.ResultsDifferences in baseline characteristics for the no internal thoracic artery graft, single internal thoracic artery, and multiple internal thoracic artery groups were as follows: median age 66, 64, and 59 years, respectively; congestive heart failure 22%, 18%, and 13%, respectively; ejection fraction 0.50, 0.52, and 0.51, respectively; reoperation 10%, 3%, and 7%, respectively; diabetes 27%, 30%, and 15%, respectively; and female gender 33%, 28%, and 20%, respectively. No differences existed in the median number of diseased vessels (3, 3, and 3, respectively) or number of grafts per patient (3, 3, and 3, respectively). Composite outcome improved with increasing internal thoracic artery grafts, whether assessing unadjusted or risk-adjusted data. Compared with no internal thoracic artery graft, the adjusted hazard ratio was 0.79 (confidence interval, 0.74-0.83) for single internal thoracic artery grafting and 0.70 (confidence interval, 0.62-0.80) for multiple internal thoracic artery grafting (both P < .001), reducing risk by 21% and 30%, respectively.ConclusionsThis study confirms improved patient outcomes with multiple internal thoracic artery grafting, achieving half again as much benefit as single internal thoracic artery grafting alone. The data suggest that increasing application of multiple internal thoracic artery grafting should be encouraged to mitigate the inherent risks and costs of long-term cardiac events

The synthetic antimicrobial peptide 19-2.5 attenuates septic cardiomyopathy and prevents down-regulation of SERCA2 in polymicrobial sepsis

LM has received grants by the Faculty of Medicine at the RWTH Aachen University (START 15/14 and START 46/16) and the Deutsche Forschungsgemeinschaft (DFG, MA 7082/1–1). This work was supported by the Immunohistochemistry and Confocal Microscopy Unit, a core facility of the Interdisciplinary Centre for Clinical Research (IZKF) Aachen, within the Faculty of Medicine at the RWTH Aachen University and the RWTH centralized Biomaterial Database (RWTH cBMB) of the University Hospital RWTH Aachen. We are very grateful to Antons Martincuks M.Sc. and Professor Gerhard Müller-Newen for live-cell imaging. This work was supported, in part, by the University of Turin (ex-60% 2015A and B) and by the William Harvey Research Foundation and forms part of the research themes contributing to the translational research portfolio of Barts and the London Cardiovascular Biomedical Research Unit that is supported and funded by the National Institute for Health Research. This work also contributes to the Organ Protection research theme of the Barts Centre for Trauma Sciences supported by the Barts and The London Charity (Award 753/1722)

Cytokine Combination Therapy with Erythropoietin and Granulocyte Colony Stimulating Factor in a Porcine Model of Acute Myocardial Infarction

PurposeErythropoietin (EPO) and granulocyte colony stimulating factor (GCSF) have generated interest as novel therapies after myocardial infarction (MI), but the effect of combination therapy has not been studied in the large animal model. We investigated the impact of prolonged combination therapy with EPO and GCSF on cardiac function, infarct size, and vascular density after MI in a porcine model.MethodsMI was induced in pigs by a 90&nbsp;min balloon occlusion of the left anterior descending coronary artery. 16 animals were treated with EPO+GCSF, or saline (control group). Cardiac function was assessed by echocardiography and pressure-volume measurements at baseline, 1 and 6&nbsp;weeks post-MI. Histopathology was performed 6&nbsp;weeks post-MI.ResultsAt week 6, EPO+GCSF therapy stabilized left ventricular ejection fraction, (41 ± 1% vs. 33 ± 1%, p &lt; 0.01) and improved diastolic function compared to the control group. Histopathology revealed increased areas of viable myocardium and vascular density in the EPO+GCSF therapy, compared to the control. Despite these encouraging results, in a historical analysis comparing combination therapy with monotherapy with EPO or GCSF, there were no significant additive benefits in the LVEF and volumes overtime using the combination therapy.ConclusionOur findings indicate that EPO+GCSF combination therapy promotes stabilization of cardiac function after acute MI. However, combination therapy does not seem to be superior to monotherapy with either EPO or GCSF

Repeated successful surgical rescues of early and delayed multiple ruptures of ventricular septum, right ventricle and aneurysmal left ventricle following massive biventricular infarction

A 58 year old man underwent 6 surgical interventions for various complications of massive biventricular myocardial infarction over a period of 2 years following acute occlusion of a possibly "hyperdominant" left anterior descending coronary artery. These included concomitant repair of apicoanterior post-infarction VSD and right ventricular free wall rupture, repeat repair of recurrent VSD following inferoposterior extension of VSD in the infarcted septum 5 weeks later, repair of delayed right ventricular free wall rupture 4 weeks subsequently, repair of a bleeding left ventricular aneurysm eroding through left chest wall 16 months thereafter, repair of right upper lobe lung tear causing massive anterior mediastinal haemorrhage, mimicking yet another cardiac rupture, 2 months later, followed, at the same admission, 2 weeks later, by sternal reconstruction for dehisced and infected sternum using pedicled myocutaneous latissimus dorsi flap. 5 years after the latissimus myoplasty, the patient remains in NYHA class 1 and is leading a normal life