Four weeks of running sprint interval training improves cardiorespiratory fitness in young and middle-aged adults.

The purpose of this study was to determine the effectiveness of a 4-week running sprint interval training protocol to improve both aerobic and anaerobic fitness in middle-aged adults (40-50 years) as well as compare the adaptations to younger adults (20-30 years). Twenty-eight inactive participants - 14 young 20-30-year-olds (n = 7 males) and 14 middle-aged 40-50-year-olds (n = 5 males) - completed 4 weeks of running sprint interval training (4 to 6, 30-s "all-out" sprints on a curved, self-propelled treadmill separated by 4 min active recovery performed 3 times per week). Before and after training, all participants were assessed for maximal oxygen consumption (VO2max), 2000 m time trial performance, and anaerobic performance on a single 30-s sprint. There were no interactions between group and time for any tested variable, although training improved relative VO2max (young = 3.9, middle-aged = 5.2%; P < 0.04), time trial performance (young = 5.9, middle-aged = 8.2%; P < 0.001), peak sprint speed (young = 9.3, middle-aged = 2.2%; P < 0.001), and average sprint speed (young = 6.8, middle-aged = 11.6%; P < 0.001) in both young and middle-aged groups from pre- to post-training on the 30-s sprint test. The current study demonstrates that a 4-week running sprint interval training programme is equally effective at improving aerobic and anaerobic fitness in younger and middle-aged adults.

A three-step technique for repair of rheumatic disease of the mitral valve.

This manuscript presents a technically straightforward technique to allow for mitral valve repair in the patient with rheumatic mitral stenosis. This non-resection technique allows for the correction of both mitral stenosis and regurgitation without requiring complex subvalvar procedures and eliminates the concerns for postoperative systolic anterior motion. The authors feel this three-part technique of bi-commissural release, anterior leaflet augmentation, and oversized annuloplasty may allow for a more reproducible approach to repair of the rheumatic mitral valve.

Insertion of an Abiomed Impella® left ventricular assist device following bioprosthetic aortic valve placement.

BACKGROUND: Post-cardiotomy cardiogenic shock is an infrequent devastating complication with few options for support. MATERIALS AND METHODS: We present a case highlighting use of the Impella 5.0 (ABIOMED; Danvers, MA) for postcardiotomy cardiogenic shock after coronary artery bypass and bioprosthetic aortic valve replacement. RESULTS: Support was maintained for 7 days before being successfully weaned with myocardial recovery and no damage to the bioprosthetic aortic valve. CONCLUSIONS: This is the first published report of successful use of an Impella 5.0 (ABIOMED; Danvers, MA) for post-cardiotomy cardiogenic shock through a new implanted bioprosthetic aortic valve.

Incidence, Natural History, and Factors Associated With Paravalvular Leak Following Surgical Aortic Valve Replacement.

Objective: Our study investigates the incidence, cumulative incidence, natural history, and factors associated with intraoperative paravalvular leak (PVL) and the development of a postoperative PVL in a contemporary consecutive cohort of patients following surgical aortic valve replacement. Methods: A total of 636 patients underwent surgical aortic valve replacement from 2006 to 2016; 410 (64.5%) underwent minimally invasive aortic valve replacement and 226 (35.5%) underwent conventional aortic valve replacement. Primary outcomes were the incidence of intraoperative PVL and cumulative incidence of postoperative PVL. Secondary outcomes were the incidence of in-hospital and long-term death and need for reoperation. Results: The overall incidence of intraoperative PVL was 1.4% (95% confidence interval [CI]: 1% to 3%). All intraoperative PVLs developed in the hand-tied group. The overall incidence of postoperative PVL was 5.3% (95% CI: 4% to 7%). In the univariable and multivariable analyses, postoperative renal failure was the only factor significantly associated with the development of a postoperative PVL. Conclusions: The incidence of intraoperative PVL is low. Cumulative incidence of postoperative PVL was 3.1% (95% CI: 1.0% to 13.6%), 4.3% (95% CI: 1.3% to 16.5%), and 5.0% (95% CI: 1.4% to 17.9%) at 1, 3, and 5 years, respectively. All intraoperative PVLs occurred with hand-tied knots. A larger cohort may identify additional risk factors.

Clinical use of the abiomed BVS 5000 as a pulsatile extracorporeal membrane oxygenation unit.

The traditional extracorporeal membrane oxygenation circuit uses a centrifugal pump. These pumps require close monitoring and are subject to complications. In addition, they do not take advantage of the potential benefits of pulsatile flow. These extracorporeal membrane oxygenation circuits use a single pump with an inline oxygenator. If cardiac failure persists after respiratory recovery has occurred, removal of the oxygenator requires an additional procedure to convert the patient to biventricular support. This report describes a circuit in which an oxygenator is connected to a pulsatile ventricular assist device. Single and dual circuit configurations are illustrated. Recommendations for pulmonary care during support are also described.

Complications following placement or extraction of endovascular pacemaker and defibrillator leads--cardiothoracic surgical intervention: case reports.

Complications related to the insertion or removal of permanent pacemakers and implantable cardiac defibrillators are rare events. However, when adverse events occur, their severity may be life threatening. Rapid recognition of a problem followed by prompt consultation with a cardiothoracic surgeon is necessary to stabilize potentially catastrophic events. The immediate availability of surgical instruments as well as a formalized algorithm for management is necessary to control hemorrhagic situations. Four case reports illustrate these points.

Aneurysm of aortocoronary saphenous vein graft: case report and literature review.

True aneurysms of aortocoronary saphenous vein bypass grafts are a relatively rare complication of bypass surgery, but because the complications of thrombosis, embolization, or rupture are potentially fatal, this condition requires immediate surgical intervention. We describe a 78-year-old man who had undergone coronary bypass 15 years previously and who presented with a saphenous vein graft that was severely degenerated and aneurysmally enlarged throughout its course, measuring as much as 5 to 6 cm in certain locations. Redo coronary artery bypass grafting using the right and left internal thoracic arteries and resection of the aneurysm were performed. We also present a review of the literature regarding diagnosis, management, and treatment of this condition.

Endoscopic botulinum toxin injection for the treatment of diabetic gastropathy in pancreas and islet-cell transplant patients.

OBJECTIVES: Gastroparesis is a well-recognized, long-term complication of diabetes. Prokinetic drugs are often not effective, prompting the development of alternative therapies. We report our experience of using one such alternative, endoscopic botulinum toxin injection, to ameliorate diabetic gastropathy in association with pancreas and islet-cell transplant patients. MATERIALS AND METHODS: Three male diabetic patients aged 42 to 55 years had been treated with botulinum toxin in our center. Two patients were both after-simultaneous pancreas-kidney transplant and 1 was awaiting islet-cell transplant after pancreatectomy. Mechanical gastric outlet obstruction was first excluded by radiological and endoscopic studies. Between 100 and 200 IU of toxin were then injected in the prepyloric region using an endoscopic technique. A subjective scoring scale was used to assess symptoms before and after botulinum therapy. RESULTS: Improvement in subjective symptom severity scoring was seen in all patients, with a posttreatment improvement from 55% to 91%. Such improvement was temporary in 2 patients and long-lasting in 1 patient. CONCLUSIONS: The time for improvement of gastric autonomic function after pancreas or islet-cell transplantation remains unclear. Some patients may continue to be symptomatic, leading to increasing morbidity. However, endoscopic botulinum injections may provide short-term relief while waiting for improvement and spare patients the morbidity associated with more-invasive therapies.

Incorporation of an in-line filter for ultrafiltration or hemodialysis to the Abiomed BVS5000 ventricular assist device.

Multiple organ system dysfunction is an associated finding in patients requiring acute ventricular assist device (VAD) support. In the setting of acute renal failure, percutaneous catheters are placed for hemodialysis and/or ultrafiltration. Incorporation of an ultrafiltration or hemodialysis system in the Abiomed BVS5000 VAD circuit is a simple maneuver that eliminates the need for an additional catheter, thereby reducing the vascular and infectious complications associated with these catheters. We recommend splicing connectors into the outflow tubing of the right VAD circuit for attachment to an ultrafiltration or hemodialysis unit. This technique is a safe, simple, and reliable method by which to perform intermittent or continuous ultrafiltration or hemodialysis.

Tissue oxygenation in sepsis; new insights from in vivo EPR.

Nitric oxide (NO) is a key mediator in the maldistribution of oxygen by tissue and organ dysfunction observed in sepsis. Despite this, few techniques are capable of measuring these parameters directly in vivo. We describe here several techniques that have been developed by our group to address this directly by in vivo EPR in animal models of sepsis. Oxygen-sensitive materials can be implanted or administered and report on local tissue pO2. Spin trapping of NO can simultaneously report on tissue NO content. Repeat measures of these parameters can be made directly from a defined tissue site, allowing development of new models and experiments to study the defects in tissue and organ function seen in sepsis.

In vivo EPR spectroscopy: biomedical and potential diagnostic applications.

EPR spectroscopic techniques have been developed for the measurement of oxygen and nitric oxide in vivo. Specifically, the methods for in vivo measurement of these molecules has been applied to the study of septic shock, utilising an experimental murine model developed in our laboratory. Oxygen was measured as pO2 by the particlulate probes Gloxy and LiPc, which were surgically implanted at specific sites in tissues, and the soluble probe Trityl, which was administered intravenously. Nitric oxide was measured as the NO-Fe-(DETC)2 complex after administration of Fe2+ and DETC. LPS was seen to significantly decrease liver oxygen measured across the lobule and at the sinusoids by the Gloxy probe; there was a corresponding increase in nitric oxide both in the liver and systemically. The nitric oxide most likely originated from increased iNOS enzyme in the liver as demonstrated by Western blotting and the localisation of nitric oxide to the liver was confirmed with EPR imaging. LPS also caused a decrease in cerebral blood and tissue oxygenation, the rate of which was found to be dependent on the blood oxygenation. The development and applications of these in vivo EPR techniques for biomedical research and diagnostics is discussed.