Lawrence Creswell

• University of Mississippi

Background While enhanced recovery after surgery (ERAS) pathways have been successfully applied for cardiac surgery, there has been limited research directly comparing ERAS protocols to ad hoc narcotic use after surgery. We hypothesized that a standardized ERAS protocol would provide similar pain management and psychoemotional outcomes while decrea...

Background : While enhanced recovery after surgery (ERAS) pathways have been successfully applied for cardiac surgery, there has been limited research directly comparing ERAS protocols to ad hoc narcotic use after surgery. We hypothesized that a standardized ERAS protocol would provide similar pain management and psycho-emotional outcomes while dec...

Introduction Given the known deleterious cardiac effects of brain death (BD) physiology, we hypothesized that time from cardiac donation referral to procurement (donor support time [DST]), would negatively impact cardiac transplant recipient survival. Methods The United Network for Organ Sharing database was queried from 2007 to 2018, identifying...

Objective Veno-arterial extracorporeal membrane oxygenation is a rescue therapy for patients in cardiogenic shock. We hypothesize that patients bridged to heart transplant with extra-corporeal membrane oxygenation (ECMO) have decreased survival. Methods The United Network of Organ Sharing database was retrospectively reviewed from 01/01/99-03/31/1...

Introduction Marfan syndrome is a connective tissue disorder caused by mutations in the fibrillar FBN‐1 gene. Aortic dissection and rupture are major causes of morbidity and mortality and are of special concern during pregnancy. Materials and Methods The authors report four cases of aortic root repair with preservation of the native aortic valve t...

Background: Extracorporeal membrane oxygenation (ECMO), a rescue therapy for pulmonary failure, has traditionally been limited by anticoagulation requirements. Recent practice has challenged the absolute need for anticoagulation, expanding the role of ECMO to patients with higher bleeding risk. We hypothesize that mortality, bleeding, thrombotic e...

Background: Limited data exist that compare the predominant cardiac preservation solutions (CPSs). Materials and methods: The United Network for Organ Sharing database was retrospectively reviewed from January 1, 2004 to March 31, 2018, for donor hearts. Of 34,614 potential donors, 21,908 remained after applying the exclusion criteria. The CPS a...

Purpose Studies have shown that thyroid hormone results in a higher number of organs available for transplant. The purpose of this study was to evaluate the effects of triiodothyronine (T3) and/or thyroxine (T4) on heart transplant recipient (HtxR) survival. Methods The United Network for Organ Sharing (UNOS) database was retrospectively reviewed...

Purpose The purpose of this study is to look at impact of race on thoracic organ recipient (TOR) survival with respect to the donor, recipient, and donor/ recipient matching. Methods The United Network for Organ Sharing (UNOS) database was retrospectively reviewed from 1/2000-3/2018 for donor hearts or lungs. After exclusions for multiorgan transp...

Background: Reports of race-related triathlon fatalities have raised questions regarding athlete safety. Objective: To describe death and cardiac arrest among triathlon participants. Design: Case series. Setting: United States. Participants: Participants in U.S. triathlon races from 1985 to 2016. Measurements: Data on deaths and cardiac...

Interest and participation in triathlon has grown rapidly over the past 20 yr and with this growth, there has been an increase in the number of new events. To maximize the safety of participation, triathlons require medical directors to plan and oversee medical care associated with event participation. Provision of proper medical care requires know...

Background Recent reports from triathlon and competitive open-water swimming indicate that these events have higher rates of death compared with other forms of endurance sport. The potential causal mechanism for swimming-related death is unclear. Objective To examine available studies on the hypothesised mechanisms of swimming-related death to dete...

We present a case of pericardial effusion due to embolization of a fragment of an inferior vena cava (IVC) filter, with subsequent perforation of the right ventricle. This is a rare and unexpected cause of pericardial effusion. Fracture or embolization of IVC filters is a relatively uncommon complication, but these events may have serious clinical...

Ectopic liver is defined as liver parenchyma situated outside the liver proper with no connection to native hepatic tissue. This rare developmental anomaly is most commonly described as an attachment to the gallbladder with an incidence <0.3%, but it has been reported in other locations within the abdomen and thorax.(2-4) Most cases are found incid...

IntroductionMechanics of cardiopulmonary bypass and related complicationsMonitoring for cardiopulmonary bypass and related complicationsAnticoagulation for cardiopulmonary bypass and related complicationsPathophysiological consequences of cardiopulmonary bypassComplications of cardioplegia

Atrial fibrillation (AF) is one of the most frequent complications of cardiac surgery, affecting more than one third of patients. The mechanism of this arrhythmia is believed to be reentry. The electrophysiologic substrate may be preexisting or may develop due to heterogeneity of refractoriness after surgery. Multiple perioperative factors have bee...

A comprehensive evidence review was conducted of the medical literature regarding the relationship between intraoperative interventions and the incidence of postoperative atrial arrhythmias, including, most commonly, atrial fibrillation (AF). Fifteen randomized, controlled studies and one large-scale concurrent cohort study were identified that rep...

New-onset atrial fibrillation (AF) occurs frequently in patients after cardiac surgery. The purpose of this study was to review the published trials and to provide clinical practice guidelines for pharmacologic prophylaxis against postoperative AF. Trials of pharmacologic prophylaxis against AF after heart surgery were identified by searching MEDLI...

The Carney complex (CNC) is a rare autosomal, dominantly inherited trait expressed as pigmented skin lesions; cardiac, cutaneous, and mucosal myxomas; and neural and functioning endocrine tumors causing endocrine overactivity.1 We describe the clinical course of an African-American woman with CNC and a hypopigmented skin lesion atypical for CNC who...

J Thorac Cardiovasc Surg 2003;125:S20-3

Atrial arrhythmias are the most common complication of cardiac surgical procedures today. Because of the additional hospital costs associated with these arrhythmias, owing to increased use of antiarrhythmic medications, diagnostic studies, and prolonged hospitalization, this subject continues to draw the interest of cardiac surgeons, cardiologists,...

Obese patients undergoing cardiac surgery are often thought to have prohibitive perioperative risk despite the lack of sufficient data to support this assumption. To assess the significance of obesity as a risk factor in patients undergoing cardiac surgery, we analyzed data from 2299 patients undergoing procedures requiring cardiopulmonary bypass f...

In end-stage pulmonary hypertension (PH), the degree of right ventricular (RV) dysfunction has been considered so severe as to require combined heart-lung transplantation. Nevertheless, left ventricular (LV) and RV hemodynamics return to relatively normal levels after single-lung transplantation (SLT) alone. Accordingly, to test the hypothesis that...

Objectives: To determine nonlinear material properties of passive, diastolic myocardium using magnetic resonance imaging (MRI) tissue-tagging, finite element analysis (FEA) and nonlinear optimization. Background: Alterations in the diastolic material properties of myocardium may pre-date the onset of or exist exclusive of systolic ventricular dy...

Although previous studies have included early reexploration for bleeding as a risk factor in analyzing adverse outcomes after cardiac operations, reexploration for bleeding has not been systematically examined as a multivariate risk factor for increased morbidity and mortality after cardiac surgery. Furthermore, multivariate predictors of the need...

A method is developed and validated for approximating continuous smooth distributions of finite strains in the ventricles from the deformations of magnetic resonance imaging (MRI) tissue tagging "tag lines" or "tag surfaces." Tag lines and intersections of orthogonal tag lines are determined using a semiautomated algorithm. Three-dimensional (3-D)...

Background: The pathophysiology of regional mechanical dysfunction in the border zone (BZ) region of left ventricular aneurysm was studied in an ovine model using magnetic resonance imaging tissue-tagging and regional deformation analysis. Methods: Transmural infarcts were created in adult Dorsett sheep (n = 8) by ligation of the distal homonymo...

Passive myocardial material properties have been measured previously by subjecting test samples of myocardium to in vitro load-deformation analysis or, in the intact heart, by pressure-volume relationships. A new method for determining passive material properties, described in this paper, couples a p-version finite element model of the heart, a non...

The frequency, importance to patient outcomes, and independent predictors of postoperative swallowing dysfunction documented by barium cineradiography were examined in 869 patients undergoing cardiac operations over a 12-month period. Swallowing dysfunction was diagnosed in 34 patients (4% incidence) and was associated with documented pulmonary asp...

The optimal timing for coronary artery bypass grafting (CABG) after acute myocardial infarction (MI) remains controversial. We examined our experience retrospectively in 3,942 patients who underwent CABG between 1986 and 1993, including 2,296 patients after acute MI. The operative mortality associated with increasing time intervals between MI and C...

A 3D, nonlinear finite element (FE) model of the diastolic canine heart was constructed from multislice magnetic resonance images (MRI). The model was solved using the p-version of the FE method to predict stress and deformation in diastole. Finite element models were employed in an 'inverse' problem to estimate the nonlinear material properties of...

The usefulness of preoperative coronary arteriography in patients with type A dissection of the aorta is controversial. To determine the prevalence of arteriosclerotic coronary artery disease in patients with type A dissection of the aorta, we reviewed our experience in 62 patients (42 with acute dissection and 20 with chronic dissection) who under...

Characterization of myocardial stress and strain is necessary for a complete understanding of myocardial function. The precise quantification of regional myocardial strain is complicated by its time-varying pattern and regional variation resulting from the anisotropy of the myocardium and by complex torsional and shortening motions of the heart dur...

An algorithm is described to compute continuous, transmural distributions of finite strains from tagged magnetic resonance (MR) images of the heart. Validation is performed by constructing a finite element (FE) model from the undeformed image and simulating complex deformations of the undeformed tags and intersections. Strains are calculated from t...

Magnetic resonance imaging (MRI) provides detailed anatomic and functional information about the in vivo myocardium in diastole or systole. The most important advantage of MRI for imaging the heart when compared with competing imaging modalities such as echocardiography and cine computed tomography is that the same region of myocardium may tracked...

A new experimental method for the evaluation of myocardial constitutive models combines magnetic resonance (MR) radiofrequency (RF) tissue-tagging techniques with iterative two-dimensional (2-D) nonlinear finite element (FE) analysis. For demonstration, a nonlinear isotropic constitutive model for passive diastolic expansion in the in vivo canine h...

The effects of direct ventricular interaction and interaction mediated by the pericardium on the diastolic left ventricle (LV) were quantified using idealized models of five pathologic conditions. Two-dimensional (2D) mathematical models were constructed in long and short axis views of four pathologic LV conditions and the normal heart (NL): dilate...

Accessory atrioventricular (AV) pathways responsible for the Wolff-Parkinson-White syndrome have been treated successfully by surgical and radiofrequency catheter ablation techniques. In this study, we explored the feasibility of permanent chemical ablation of accessory pathways by direct injection of 100% ethanol into the canine AV groove. Right c...

Evaluation of time-varying cardiac structure and function is challenging because of the three-dimensional (3-D) anatomy and time-varying (4-D) behavior of the heart. Historically, contrast angiography has served as the cornerstone of cardiac diagnosis because of its excellent spatial and temporal resolution. However, magnetic resonance (MR) imaging...

Between January 1, 1986, and December 31, 1991, 4,507 adult patients underwent cardiac surgical procedures requiring cardiopulmonary bypass. Of these patients, 3,983 patients who did not undergo operation for supraventricular tachycardia and who were in normal sinus rhythm preoperatively form the study group for the present study. Postoperatively,...

Analysis of the pressure-dimension relationship provides a sensitive index of myocardial contractility, but widespread application of this method is limited because it requires invasive measurement techniques. The recent development of two-dimensional echocardiographic automatic boundary detection permits accurate and reproducible on-line measureme...

The characterization of regional myocardial stress distribution has been limited by the use of idealized mathematical representations of biventricular geometry. State-of-the-art computer-aided design and engineering (CAD/CAE) techniques can be used to create complete, unambiguous mathematical representations (solid models) of complex object geometr...

A material identification algorithm is described for determining the iri vivo material properties of the diastolic myocardium. A nonlinear optimization algorithm is used to solve a least squares objective function. The objective function relates the least squares difference of model-predicted displacements obtained from a finite element (FE) soluti...

Between January 1, 1986, and May 6, 1991, 7,884 cardiac surgical procedures requiring cardiopulmonary bypass were performed at our institution, including 672 (9.8% of adult procedures) performed in 669 patients that were associated with preoperative (n = 240), intraoperative (n = 353), or postoperative (n = 79) use of an intraaortic balloon pump. T...

Electrocardiographically gated magnetic resonance (MR) image acquisition is not optimal for the quantification of in vivo cardiac deformation, because of the cycle-length dependence of cardiac mechanical events. The authors developed a method for acquisition of cardiac MR images gated to the first derivative of left-ventricular-developed pressure a...

A hybrid three-dimensional solid mathematical model of cardiac ventricular geometry developed using magnetic resonance (MR) images of an in vivo canine heart is discussed. The modeling techniques were validated using MR images of an ex vivo heart and direct measurements of cardiac geometry and mass properties. A spin-echo MR sequence with in-plane...

The instantaneous regional stress distribution within the myocardium, which cannot be directly measured, has been estimated using improved numerical methods and nonaxisymmetric biventricular geometry. To do this, we have employed computer-aided solid mathematical modeling to generate a three-dimensional representation for an ex vivo canine biventri...

Bonaventura and Myers (1969) and Murata (1969) showed that illumination of microalgae with light absorbed preferentially by either PS1 or PS2 led to changes in the chlorophyll fluorescence emission that were indicative of a redistribution of energy between the two photosystems. Illumination with light 1, absorbed preferentially by PS1, resulted in...