Biomedical subjects

D H Harpole

Publications and source records attributed to D H Harpole.

42 records · Page 3Linked to original sources

PubMed1989

Validation of pressure-volume data obtained in patients by initial transit radionuclide angiocardiography.

In order to validate the measurement of pressure-volume loops and stroke work in humans, simultaneous digital subtraction ventriculography (DSA) and first-pass radionuclide angiocardiography (RNA) coupled with high-fidelity micromanometer left ventricular pressure measurements were undertaken in 34 patients, mean age 75 +/- 9 years, with aortic stenosis. Twenty-nine patients had a repeat study after balloon valvuloplasty, for a total of 63 DSA and RNA pressure-volume loops. All data were analyzed in a systemic fashion in order to minimize intra- and interobserver error. Linear regression analysis was used to calculate the degree of agreement between the two technologies. Left ventricular ejection fraction (RNA: 0.47 +/- 0.17, DSA: 0.49 +/- 0.18) had a correlation coefficient of 0.96; left ventricular end-diastolic volume (RNA: 171 +/- 42 ml, DAS: 168 +/- 52 ml) and end-systolic volume (RNA: 95 +/- 50 ml, DSA: 89 +/- 50 ml) had correlation coefficients of 0.89 and 0.95, respectively. Left ventricular stroke volume (RNA: 75 +/- 26 ml, DSA: 75 +/- 27 ml) had a correlation coefficient of 0.92, while integrated pressure-volume loop or stroke work (RNA: 15.6 +/- 6.6 ergs 10(6), DSA: 15.9 +/- 6.3 ergs 10(6] had a correlation coefficient of 0.89. These data demonstrate that RNA measurements of left ventricular chamber dynamics concur with that obtained with DSA. With semiautomated data analysis, the portable first-pass RNA pressure-volume data are also less labor-intensive. Moreover, multiple measurements of ventricular performance during hemodynamic manipulations in the catheterization laboratory or operating room would allow for a more precise estimation of left ventricular performance.

Aged↗

PubMed1989

Right and left ventricular performance during and after abdominal aortic aneurysm repair.

To evaluate the effect of aortic occlusion and limb reperfusion on global and regional function of the right and left ventricle during infrarenal abdominal aortic aneurysm repair, 23 patients underwent five intraoperative first-pass radionuclide angiocardiograms: 1) before the skin incision, 2) at aortic cross-clamp, 3) 20 minutes after aortic occlusion, 4) at unclamping, and 5) after skin closure. A subset of twelve patients had simultaneous transesophageal echocardiography to evaluate left ventricular wall stress. Parameters measured included the electrocardiogram (ECG), heart rate, blood pressure, pulmonary artery pressure, the cardiac output, the left and right ventricular ejection fractions, left ventricular volumes, and left ventricular wall stress. Significant changes (p less than 0.01) were observed at aortic clamping in the left ventricular ejection fraction (from 0.56 to 0.48), end-diastolic volume (from 171 to 225 ml), end-systolic volume (from 85 to 127 ml), mean blood pressure (from 82 to 91 mmHg), and meridional end-systolic wall stress (from 53 to 67 10(3) dyne/cm2). Once the clamp was removed, significant variations were seen in the left ventricular ejection fraction (from 0.51 to 0.58), end-diastolic volume (from 205 to 187 ml), end-systolic volume (from 105 to 94 ml), mean blood pressure (from 84 to 69 mmHg), and meridional end-systolic wall stress (from 67 to 46 10(3) dyne/cm2). No differences were observed between the two aortic occlusion studies, and the baseline level of function was recovered in all parameters during the last study. These data quantify the changes in heart function that occur during abdominal aortic aneurysm operation and demonstrate that the majority of the adaptations that occurred were due to a variation in afterload.

Aged↗

PubMed1989

Assessment of left ventricular functional preservation during isolated cardiac valve operations.

To evaluate intraoperative changes in myocardial performance during valvular operations, ventricular functional measurements were obtained in 16 patients before and after elective cardiac valvular replacement. Six patients had mitral regurgitation, four had mitral stenosis, and six had calcific aortic stenosis; all patients underwent isolated mitral or aortic valve replacement. Cold potassium crystalloid cardioplegia, topical hypothermia, and low-flow systemic hypothermia were employed uniformly. Just before and 10 minutes after cardiopulmonary bypass was discontinued, left ventricular pressure and volume data were recorded at four to five different steady-state levels of filling produced by blood infusion or withdrawal from the aortic cannula (mean end-diastolic pressure range, 10-22 mm Hg; mean end-diastolic volume range, 120-168 ml). Portable first-pass radionuclide ventriculography and simultaneous micromanometry were used for construction of left ventricular pressure-volume loops from which stroke work and end-diastolic volume were calculated. Two-dimensional transesophageal echocardiograms also were recorded, and epicardial pacing maintained heart rate as constant as possible. As compared with prebypass measurements, echocardiographic left ventricular wall volume changed insignificantly after the valvular procedures (178-181 ml/m2, p greater than 0.5). The stroke work-end-diastolic volume relationship before and after operation was highly linear in all studies (mean = 0.97). The slope and x intercept of this relationship did not change significantly after operation, indicating a stable level of left ventricular function (from 12.7 x 10(4) to 10.0 x 10(4) ergs/ml and from 67 to 57 ml, respectively; p greater than 0.3).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiopulmonary Bypass↗

PubMed1988

Prognostic factors in head and neck melanoma. Effect of lesion location.

Cutaneous malignant melanomas of the head and neck are prognostically engimatic. In addition to known prognostic determinants of stage and lesion microstage, lesion location also appears to have prognostic importance. The authors have reviewed a series of 83 microstaged head and neck melanoma patients in order to analyze the relative importance of these factors. There were 36 males and 47 females with a median age of 56 years. Eighty-one percent had pathologic Stage I disease, 7% were Stage II, and 12% were Stage III. The primary location was face in 32 patients, neck in 18, ear in 12, and scalp in 21 patients. The actuarial 5-year survival according to lesion thickness was 86% for melanoma less than 1.0 mm, 56% for 1 to 2 mm thick lesions, 47% for 2.1 to 4 mm thick lesions, and 25% for melanomas greater than 4.0 mm. The 5-year survival according to lesion location was 78% for facial and 58% for neck melanomas; for ear and scalp, the respective survivals were 33% and 37%. Median thickness was 2.0 mm for facial and 1.85 mm for neck lesions. It was 2.7 mm for ear and 2.0 mm for scalp lesions (differences not significant). There were no microstage factors that correlated with the adverse prognosis seen with scalp and ear melanomas. Multivariate analysis in the entire series (all clinical stages) showed the following to be significant: stage, thickness, and location of the primary melanoma (all less than 0.0002). In clinical Stage I melanoma, the significant prognostic factors were location (P = 0.035), thickness (P = 0.008), level (P = 0.024), and ulceration (P = 0.035). The prognosis of head and neck melanoma is uniquely influenced by location of the primary lesions in addition to stage, thickness, level, and ulceration, as observed with other cutaneous melanomas at other sites. Ear and scalp melanomas are high-risk lesions whose poor prognosis is not readily explained by any of the microstage factors reviewed.

Adolescent↗

PubMed1988

Alveolar cell carcinoma of the lung: a retrospective analysis of 205 patients.

From 1970 to 1986, survival of 205 patients with alveolar cell carcinoma was retrospectively studied. Analysis examined the predictive value of presenting symptoms and diagnostic screening results for pathological Stage III or IV disease (advanced) and survival. The lesion presented as a peripheral mass in 121 patients (59%) and as an infiltrate in 84 (41%). Follow-up data were available on 199 patients (97%). Variables analyzed included indices of background or risk factors, presenting symptoms, diagnostic test results, and clinical management. Seventy-nine patients (39%) had a histological diagnosis of advanced disease by TMN staging criteria. Of the 152 deaths (74%), 117 (77%) were related to the pulmonary carcinoma. Univariate analysis associated short-term and long-term anorexia, weight loss, generalized weakness, and profound dyspnea with advanced disease and ultimately with death due to cancer. Multivariate logistic regression analyses suggested that weight loss and dyspnea disclosed independent information about the likelihood of advanced disease for this population (p less than 0.0003). Cox proportional hazard regression analyses of survival revealed a significant association between weight loss and death due to alveolar cell carcinoma after pathological stage was taken into account (p = 0.001). In this series, the 80 patients with Stage I disease had the best prognosis (5-year survival of 55%). There was no significant difference in disease-free survival between patients having wedge resection (N = 17) and those having lobectomy (N = 63) for Stage I disease.

Adenocarcinoma, Bronchiolo-Alveolar↗

PubMedDate not supplied

Correlation of FDG-PET imaging with Glut-1 and Glut-3 expression in early-stage non-small cell lung cancer.

PURPOSE: To correlate FDG activity on PET with the expression of glucose transporter proteins Glut-1 and Glut-3 in patients with early stage non-small cell lung cancer (NSCLC). METHODS: Over a 5 year period, all patients with a PET scan and clinical stage I NSCLC underwent an immunohistochemical analysis of their tumor for Glut-1 and Glut-3 expression. The amount of FDG uptake in the primary lesion was measured by a standardized uptake ratio (SUR) and correlated with immunohistochemical results. RESULTS: Seventy-three patients with a mean age of 66 years had clinical stage I disease. The final pathologic stage showed 64 patients with stage IA/B disease, eight with stage IIA disease, and one patient with pathologic stage IIIA (T1N2) disease. Glut-1 transporter expression was significantly higher than Glut-3 (P<0.0001), and although there was some association between the SUR and Glut-1 (P=0.085) and SUR and Glut-3 (P=0.074) expression, this did not reach statistical significance. CONCLUSIONS: Glut-1 and Glut-3 transporter expression did not demonstrate a statistically significant correlation with FDG uptake in potentially resectable lung cancer. It appears that these transporters alone do not affect the variation in FDG activity in early stage NSCLC.

Aged↗