Evaluating Osteoarthritis Management Programs: outcome domain recommendations from the OARSI Joint Effort Initiative

OBJECTIVE

To develop sets of core and optional recommended domains for describing and evaluating Osteoarthritis Management Programs (OAMPs), with a focus on hip and knee Osteoarthritis (OA).

DESIGN

We conducted a 3-round modified Delphi survey involving an international group of researchers, health professionals, health administrators and people with OA. In Round 1, participants ranked the importance of 75 outcome and descriptive domains in five categories: patient impacts, implementation outcomes, and characteristics of the OAMP and its participants and clinicians. Domains ranked as "important" or "essential" by ≥80% of participants were retained, and participants could suggest additional domains. In Round 2, participants rated their level of agreement that each domain was essential for evaluating OAMPs: 0 = strongly disagree to 10 = strongly agree. A domain was retained if ≥80% rated it ≥6. In Round 3, participants rated remaining domains using same scale as in Round 2; a domain was recommended as "core" if ≥80% of participants rated it ≥9 and as "optional" if ≥80% rated it ≥7.

RESULTS

A total of 178 individuals from 26 countries participated; 85 completed all survey rounds. Only one domain, "ability to participate in daily activities", met criteria for a core domain; 25 domains met criteria for an optional recommendation: 8 Patient Impacts, 5 Implementation Outcomes, 5 Participant Characteristics, 3 OAMP Characteristics and 4 Clinician Characteristics.

CONCLUSION

The ability of patients with OA to participate in daily activities should be evaluated in all OAMPs. Teams evaluating OAMPs should consider including domains from the optional recommended set, with representation from all five categories and based on stakeholder priorities in their local context.

Biomarkers and longitudinal changes in lumbar spine degeneration and low back pain: the Johnston County Osteoarthritis Project

OBJECTIVE

To determine if baseline biomarkers are associated with longitudinal changes in the worsening of disc space narrowing (DSN), vertebral osteophytes (OST), and low back pain (LBP).

DESIGN

Paired baseline (2003-2004) and follow-up (2006-2010) lumbar spine radiographs from the Johnston County Osteoarthritis Project were graded for severity of DSN and OST. LBP severity was self-reported. Concentrations of analytes (cytokines, proteoglycans, and neuropeptides) were quantified by immunoassay. Pressure-pain threshold (PPT), a marker of sensitivity to pressure pain, was measured with a standard dolorimeter. Binary logistic regression models were used to estimate odd ratios (OR) and 95% confidence intervals (CI) of biomarker levels with DSN, OST, or LBP. Interactions were tested between biomarker levels and the number of affected lumbar spine levels or LBP.

RESULTS

We included participants (n = 723) with biospecimens, PPT, and paired lumbar spine radiographic data. Baseline Lumican, a proteoglycan reflective of extracellular matrix changes, was associated with longitudinal changes in DSN worsening (OR = 3.19 [95% CI 1.22, 8.01]). Baseline brain-derived neuropathic factor, a neuropeptide, (OR = 1.80 [95% CI 1.03, 3.16]) was associated with longitudinal changes in OST worsening, which may reflect osteoclast genesis. Baseline hyaluronic acid (OR = 1.31 [95% CI 1.01, 1.71]), indicative of systemic inflammation, and PPT (OR = 1.56 [95% CI 1.02, 2.31]) were associated with longitudinal increases in LBP severity.

CONCLUSION

These findings suggest that baseline biomarkers are associated with longitudinal changes occurring in structures of the lumbar spine (DSN vs OST). Markers of inflammation and perceived pressure pain sensitivity were associated with longitudinal worsening of LBP.

A machine learning approach to knee osteoarthritis phenotyping: data from the FNIH Biomarkers Consortium

OBJECTIVE

Knee osteoarthritis (KOA) is a heterogeneous condition representing a variety of potentially distinct phenotypes. The purpose of this study was to apply innovative machine learning approaches to KOA phenotyping in order to define progression phenotypes that are potentially more responsive to interventions.

DESIGN

We used publicly available data from the Foundation for the National Institutes of Health (FNIH) osteoarthritis (OA) Biomarkers Consortium, where radiographic (medial joint space narrowing of ≥0.7 mm), and pain progression (increase of ≥9 Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] points) were defined at 48 months, as four mutually exclusive outcome groups (none, both, pain only, radiographic only), along with an extensive set of covariates. We applied distance weighted discrimination (DWD), direction-projection-permutation (DiProPerm) testing, and clustering methods to focus on the contrast (z-scores) between those progressing by both criteria ("progressors") and those progressing by neither ("non-progressors").

RESULTS

Using all observations (597 individuals, 59% women, mean age 62 years and BMI 31 kg/m2) and all 73 baseline variables available in the dataset, there was a clear separation among progressors and non-progressors (z = 10.1). Higher z-scores were seen for the magnetic resonance imaging (MRI)-based variables than for demographic/clinical variables or biochemical markers. Baseline variables with the greatest contribution to non-progression at 48 months included WOMAC pain, lateral meniscal extrusion, and serum N-terminal pro-peptide of collagen IIA (PIIANP), while those contributing to progression included bone marrow lesions, osteophytes, medial meniscal extrusion, and urine C-terminal crosslinked telopeptide type II collagen (CTX-II).

CONCLUSIONS

Using methods that provide a way to assess numerous variables of different types and scalings simultaneously in relation to an outcome of interest enabled a data-driven approach that identified key variables associated with a progression phenotype.

Evaluation of the self-directed format of Walk With Ease in patients with systemic lupus erythematosus: the Walk-SLE Pilot Study

OBJECTIVE

To conduct a proof-of-concept pilot evaluation of the self-directed format of Walk With Ease (WWE), a 6-week walking program developed for adults with arthritis, in patients with systemic lupus erythematosus (SLE).

METHODS

This was a single arm, 6-week pre- and post-evaluation of the self-directed WWE program to assess feasibility, tolerability, safety, acceptability, and effectiveness. Adult patients with physician-diagnosed SLE were recruited to participate during regularly scheduled visits to an academic rheumatology clinic. Self-reported outcomes of pain, stiffness, and fatigue were assessed by visual analog scales (VAS) and the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-fatigue) scale at baseline and at completion of the 6-week program. Patients also completed a satisfaction survey at the end of the program. Multivariate linear regression models were used to calculate mean changes between baseline and 6-week follow-up scores, adjusting for covariates. Mean change scores were used to estimate effect sizes (ES).

RESULTS

At 6 weeks, 48 of the 75 recruited participants completed the WWE program. Participants experienced modest improvements in stiffness and fatigue (ES = 0.12 and ES = 0.23, respectively, for VAS scores; ES = 0.16 for FACIT-fatigue score) following the intervention. The majority of participants reported satisfaction with the program (98%) and benefitted from the workbook (96%).

CONCLUSIONS

The self-directed format of WWE appears to reduce stiffness and fatigue in patients with SLE. It also seems to be a feasible and acceptable exercise program to patients with SLE. Larger studies are needed to confirm these findings.

P4-12-03: Post-Diagnosis Weight Gain in Breast Cancer Survivors: When Should We Intervene?

Significance. Weight gain after breast cancer diagnosis is common and has been linked to poor prognosis. Studies of the etiology and longitudinal pattern of post-diagnosis weight gain are limited, yet are critical to developing effective prevention strategies to enhance ***survival.. Approach. We investigated the longitudinal pattern and determinants of post-diagnosis weight gain among 1,436 breast cancer survivors. The population-based cohort included women newly diagnosed with a first primary in situ or invasive breast cancer. Subjects were interviewed within 6 months of diagnosis and again 5 years later to ascertain factors related to survival, including self-reported anthropometric measures. We employed: adjusted random effects linear regression to identify factors related to weight change during the follow-up; multiple imputation to account for missing data; and Wald tests to test for significance of interactions with follow-up time.

Results. Average weight gain was 0.74 kilograms (kg) during the first year after diagnosis and 2.39 kg at the follow-up interview. The strongest predictors of post-diagnosis gain were body size characteristics before diagnosis, which varied with time since diagnosis. Compared to women with body mass index (BMI, kg/m2) 18.5−24.9 1 year before diagnosis, those with greater BMI were more likely to gain weight during the first year after diagnosis [difference in mean yearly increase: BMI 25.0−29.9 vs. 18.5−24.9 (95% confidence interval): 1.93 kg/year (0.50, 3.37); BMI >=30.0 vs. 18.5−24.9: 0.47 kg/year (0.24, 0.71)] and after the first year [5.17 kg/year (3.68, 6.66) and 0.93 kg/year (0.58, 1.28), respectively], with the effect greater during the first year (p-interaction: <0.001). A pre-diagnosis weight gain of more than 10% since age 20 was also associated with post-diagnosis weight gain [during year 1, difference in mean yearly increase compared to maintenance within 3% age 20 weight: 2.32 kg/year (0.59, 4.05); after year 1: 0.53 kg/year (0.17, 0.89)] with the effect again stronger during the first year (p-interaction: 0.02). Modest associations, which varied only slightly with time, included: increases in post-diagnosis weight gain with chemotherapy, tumor characteristics indicative of poor prognosis, and a previous diagnosis of hypertension, blood clots, or diabetes; and decreases with increasing recreational physical activity and a history of myocardial infarction.

Conclusions. Greater pre-diagnosis BMI and pre-diagnosis adult weight gain are strongly related to post-diagnosis weight gain among breast cancer survivors. The rate of post-diagnosis weight gain appears to be faster during the first year than after, suggesting that interventions to prevent post-diagnosis weight gain may be most important during the first year after diagnosis, especially among women who with BMI >= 25.0 1 year prior to diagnosis.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-12-03.

Polymorphisms of genes coding for insulin-like growth factor 1 and its major binding proteins, circulating levels of IGF-I and IGFBP-3 and breast cancer risk: results from the EPIC study

Insulin-like growth factor I (IGF-I) stimulates cell proliferation and can enhance the development of tumours in different organs. Epidemiological studies have shown that an elevated level of circulating IGF-I is associated with increased risk of breast cancer, as well as of other cancers. Most of circulating IGF-I is bound to an acid-labile subunit and to one of six insulin-like growth factor binding proteins (IGFBPs), among which the most important are IGFBP-3 and IGFBP-1. Polymorphisms of the IGF1 gene and of genes encoding for the major IGF-I carriers may predict circulating levels of IGF-I and have an impact on cancer risk. We tested this hypothesis with a case–control study of 807 breast cancer patients and 1588 matched control subjects, nested within the European Prospective Investigation into Cancer and Nutrition. We genotyped 23 common single nucleotide polymorphisms in IGF1, IGFBP1, IGFBP3 and IGFALS, and measured serum levels of IGF-I and IGFBP-3 in samples of cases and controls. We found a weak but significant association of polymorphisms at the 5′ end of the IGF1 gene with breast cancer risk, particularly among women younger than 55 years, and a strong association of polymorphisms located in the 5′ end of IGFBP3 with circulating levels of IGFBP-3, which confirms previous findings. Common genetic variation in these candidate genes does not play a major role in altering breast cancer risk in Caucasians.

Association of recall rates with sensitivity and positive predictive values of screening mammography

OBJECTIVE

The performance of screening mammography is measured mainly by its sensitivity, positive predictive value, and cancer detection rate. Recall rates are also suggested as a surrogate measure. The main objective of this study was to measure the effect on sensitivity and positive predictive value as recall rates increase in the community practice of mammography.

MATERIALS AND METHODS

Mammography and pathology data are linked in the Carolina Mammography Registry, a population-based registry of screening mammography. Our mammography database is created from prospectively collected data from mammography facilities; the data include information on the woman and the imaging studies. Our pathology database is created from prospectively collected breast pathology data received from pathology sites and the Central Cancer Registry. Women in the registry who were 40 years old and older and who underwent screening mammography between January 1994 and June 1998 were included. "Recall rate" was defined as the percentage of screening studies for which further workup was recommended by the radiologist.

RESULTS

The study included 215,665 screening mammograms. The mean age of the women was 56 years. The recall rates of the average practice ranged from 1.9% to 13.4%. Sensitivity rose from a mean of 65% in the lowest recall rates to 80.2% at the highest level of recall rates. The positive predictive value of screening decreased from 7.2% in the lowest level of recall to 3.3% in the highest. As recall rates increased, sensitivity increased very little beyond a recall rate of 4.8%, and positive predictive value began decreasing significantly at a recall rate of 5.9%.

CONCLUSION

Practices with recall rates between 4.9% and 5.5% achieve the best trade-off of sensitivity and positive predictive value.

Repair of coarctation of the aorta during infancy minimizes the risk of late hypertension

BACKGROUND

Recent surgical reports on coarctation of the aorta have primarily focused on the relative merits of various operative techniques. However, appropriate timing for elective repair remains unclear.

METHODS

In a retrospective analysis we examined the surgical outcomes in 176 consecutive patients undergoing repair of coarctation of the aorta in our institution over a 25-year period. Ninety-nine percent of the patients had follow-up for a median of 7.5 years.

RESULTS

A total of 13 patients have died (7.4% overall mortality). Nine of these patients had associated complex intracardiac anomalies. There was no mortality in the 113 patients with isolated coarctation. Residual or recurrent coarctation occurred in 27 patients (15.3%). The age at operation and the type of surgical repair did not have an effect on the incidence of recurrence. Persistent or late hypertension was identified in 18 of the 107 patients who have been followed up for more than 5 years (16.8%). A total of 48 patients operated on during infancy have been followed up for more than 5 years. Only 2 have developed late hypertension (4.2%). Both of these patients had recurrence. In contrast, 16 of the 59 patients operated on after a year of age had late hypertension (27.1%).

CONCLUSIONS

To minimize the risk of persistent hypertension, elective repair of coarctation should be performed within the first year of life.

Planning, development, and execution of an international training program in laparoscopic surgery

In the late 1980s, minimally invasive surgery experienced unprecedented growth. Centers appeared worldwide, providing a variety of training opportunities and laboratory experiences. Because standard surgical training varies greatly from country to country, it became apparent that this variety was even more pronounced in the area of minimally invasive and laparoscopic surgery, posing significant credentialling difficulties for professional standards committees wishing to certify surgical staff who submit unevaluable credentials from all over the world. In January 1993, the Center for Minimally Invasive Surgery at New England Medical Center and Tufts University School of Medicine was asked to plan and execute a program of education, training, and credentialling for a multispecialty surgical staff in the Eastern province of Saudi Arabia. A four-stage program was designed and developed to provide credentialling from the technician level through the instructor surgeon level. A multidisciplinary course was developed and a team placed on site for 1 month to execute the program. This program began with an 8-h didactic/video session in basic laparoscopy, covering areas common to the involved subspecialties: surgery, urology, and gynecology. This session was followed by hands-on training sessions in general surgery and urology and credentialling in gynecology. Physicians who successfully completed the examination in basic laparoscopy were later eligible for credentialling at one of three clinical specialty levels: basic clinical laparoscopy, advanced clinical laparoscopy, or instructor in clinical laparoscopy. Education and credentialling in minimally invasive surgery can be accomplished by executing a program of basic science and clinical training for physicians, technicians, and nurses that accommodates a wide range of experience of participants, from novice to master surgeon. Support from the hospital administrators and department chairs was instrumental in the program's success. Among the goals we accomplished was identification of persons in an institution who could serve as future instructors and certifiers for the hospital's self-sustaining program as well as providing a relationship in which international institutions can serve as a resource for further continuing medical education and clinical and laboratory training. This program may well serve as the model template for international credential standards of the future.

Granulocyte sequestration and early failure in the autoperfused heart-lung preparation

We investigated the role of pulmonary granulocyte sequestration in the development of early failure of the autoperfused working heart-lung preparation. A significant decline in the total circulating leukocyte count in 21 preparations at 60 minutes of perfusion (5.0 to 1.4 x 10(3)/microL; 28% of baseline; p less than 0.001) was observed. Differential cell counts in 14 of these preparations revealed a predominant decrease in granulocyte count (8.7% of baseline) and a moderate decline in lymphocyte count (46% of baseline). In study I, indium 111-labeled autologous granulocytes were injected intravenously into 10 adult New Zealand White rabbits. In group I (n = 5), an autoperfused working heart-lung preparation was harvested and perfused for 60 minutes. In group II (controls, n = 5), the heart-lung block was harvested following 60 minutes of in situ perfusion. Organ blocks were imaged before and after saline flush. There was a significant decline in granulocyte counts at 60 minutes of perfusion in group I versus no change in group II (I, 2.3 +/- 0.4 to 0.3 +/- 0.1; p less than 0.01; II, 1.7 +/- 0.2 to 2.3 +/- 0.5; not significant; x 10(3)/microL +/- standard error of the mean). Postflush lung activity was significantly increased in group I versus group II (I, 3,751 +/- 566; II, 1,867 +/- 532; p less than 0.05; counts +/- standard error of the mean). In study II, 15 autoperfused preparations were divided into two groups. Group I (n = 10) preparations were controls. Group II (n = 5) animals were depleted of leukocytes by pretreating with nitrogen mustard. Group I (controls) produced a bimodal survival distribution (Ia, 8.2 +/- 1.0; Ib, 26.4 +/- 2.0; hours +/- standard error of the mean). Group II survival was significantly longer than that of group Ia and similar to that of group Ib (II, 25.3 +/- 2.2; p less than 0.01 versus group Ia, not significant versus group Ib; hours +/- standard error of the mean). Hemodynamic profiles for group II closely paralleled those of group Ib. In conclusion, pulmonary sequestration of granulocytes occurs early in the autoperfused working heart-lung preparation (within 60 minutes of autoperfusion), and preoperative leukocyte depletion prolongs survival of the autoperfused working heart-lung preparation by eliminating the subset group Ia (short survivors) seen in untreated preparations.

Spinal cord protection during aortic occlusion: efficacy of intrathecal tetracaine

Spinal cord ischemia and resultant paraplegia are devastating sequelae in up to 40% of patients undergoing repair of thoracoabdominal aneurysms. We investigated the effect of intrathecal tetracaine on the neurological sequelae of spinal cord ischemia and reperfusion with aortic occlusion. Cocaine-derived anesthetics (lidocaine and its analogues) have been shown to decrease neuronal cell metabolism and also have specific neuronal membrane stabilizing effects. New Zealand white rabbits were anesthetized and spinal cord ischemia was then induced by infrarenal aortic occlusion. Animals were divided into six treatment groups. Tetracaine (groups 2 and 4) or normal saline solution (group 5) was administered intrathecally before aortic cross-clamping. Groups 1 and 3 functioned as controls. Group 6 animals received intravenous thiopental. Rabbits were classified as either neurologically normal or injured (paralyzed or paretic). Among controls, 25 minutes of aortic occlusion produced varied neurological sequelae (group 1, 3/6 injured, 50%) whereas 30 minutes resulted in more consistent injury (group 3, 5/6 injured, 83%). All rabbits that received intrathecal saline solution were paralyzed (group 5, 4/4 injured, 100%). Animals treated with intrathecal tetracaine and aortic occlusion of 30 minutes (group 4) showed significantly better preservation of neurological function (6/7 normal, 86%) than controls and saline-treated animals (groups 3 and 5). All animals treated with intrathecal tetracaine and aortic occlusion for 25 minutes (group 2) showed no signs of injury (5/5 normal, 100%), but this was not significant versus controls (group 1). Intravenous thiopental (group 6, 5/5 injured, 100%) had no beneficial effect. Intrathecal tetracaine significantly and dramatically abrogated the neurological injury secondary to spinal cord ischemia and reperfusion after aortic occlusion at 30 minutes in the rabbit model.

Patch aortotomy for aortic valve replacement after previous coronary artery bypass grafting

Exposure for aortic valve operations after previous coronary artery bypass grafting may be technically difficult owing to the presence of patent vein grafts on the proximal aorta. A patch or "island" aortotomy technique that allows excellent exposure of the aortic valve is presented here. In select patients this approach may facilitate cardioplegia administration.

Rapid in-line blood warming using microwave energy: preliminary studies

The management of massive blood loss resulting from trauma or surgery necessitates rapid transfusion capability. Hypothermia secondary to shock, transfusion, and prolonged surgical procedures significantly increases morbidity and mortality in these patients. Transfusion at high flow rates frequently exceeds the warming capacity of conventional blood-warming devices, whose inherent resistance also limits the maximal flow rates. Microwave ovens are capable of blood warming, but have been associated with unacceptable hemolysis. We have investigated the possibility of using microwave energy to provide rapid in-line blood warming. Fresh blood from 10 human subjects was warmed from an average of 18 degrees C to temperatures ranging from 37 to 39 degrees C at flow rates from 250 to 500 mL/min. Laboratory analysis of free plasma hemoglobin, haptoglobin, hematocrit, hemoglobin, and electrolytes showed no difference between heated and control samples. LDH was elevated in those samples warmed repeatedly, but remained within the normal range. These data indicate the potential for further investigation utilizing properly controlled microwave energy for in-line blood and fluid warming.

Leukocyte redistribution and eicosanoid changes during the autoperfused working heart-lung preparation

We studied the role of leukocyte redistribution and eicosanoid changes in the early stages of instituting 16 rabbit autoperfused working heart-lung preparations (AWHLP). Physiological changes occurring during the transition from the intact animal to the AWHLP may determine the survival and viability of the organ blocks for transplantation. White blood cell (WBC) count decreased from 5,160/microL to 1430/microL (P less than .01) at 60 min of autoperfusion. Differential WBC counts performed in ten of these AWHLP revealed a 63% decrease in lymphocyte count and an 88% decrease in the granulocyte count at 60 min. Thus, the predominant leukocyte remaining in the circulation was the lymphocyte. Blood samples were collected from the intact animal and from the AWHLP for assay of the stable metabolites of thromboxane A2 (TxA2) and prostacyclin (PGI2). Transition from the in situ heart-lung block to the in vitro AWHLP stage caused significant changes in these metabolites. The PGI2 metabolite 6-ketoprostaglandin F1a (6KPGF1a) increased from 2680 +/- 487 to 4339 +/- 478 (pg/mL), P less than .05, while the TxA2 metabolite, thromboxane B2 (TxB2) decreased from 618 +/- 105 to 289 +/- 63 (pg/mL). However, assays of 11-dehydro-TxB2 (11-DHT), a longer lived metabolite of TxA2 (n = 7) increased (668.4 +/- 84.6 to 946.4 +/- 43.7, P less than .05). The transition from the in situ heart-lung block of the intact animal to the AWHLP involves significant physiological changes. Redistribution of leukocytes occurs with a predominant decrease in the granulocyte count, while levels of bioactive lipid mediators show a distinct large rise in the PGI2 metabolites and a lesser increase in TxA2 metabolites.(ABSTRACT TRUNCATED AT 250 WORDS)

Extended ex vivo preservation of the heart and lungs. Effects of acellular oxygen-carrying perfusates and indomethacin on the autoperfused working heart-lung preparation

The autoperfused working heart-lung preparation has been proposed as a method for long-term heart-lung preservation. We investigated the effects of acellular oxygen-carrying perfusates (study 1) and the effect of donor pretreatment with indomethacin (study 2) on the working ex vivo heart-lung block. In study 1 perfusion with stroma-fee hemoglobin resulted in significantly reduced survival (118 +/- 46 minutes) compared with autologous blood (561 +/- 125 minutes, p less than 0.05) or perfluorocarbon (438 +/- 114 minutes, p less than 0.05). Decrease in survival with stroma-free hemoglobin perfusate is associated with a marked decrease in left ventricular performance and a significant increase in pulmonary vascular resistance. Perfusion with autologous blood is associated with a significant increase in pulmonary vascular resistance after 240 minutes of explantation, which is significantly delayed by perfusion with perfluorocarbon. Perfusion for 6 hours with blood pretreated with indomethacin (study 2) resulted in a decrease in the concentration of prostacyclin and thromboxane A2 metabolites but an increase in the prostaglandin/thromboxane A2 metabolite ratio. This is associated with abrogation of the increase in pulmonary vascular resistance (12,787 +/- 1682 dynes/sec/cm-5, T = 0; 13,134 +/- 2654 dynes/sec/cm-5, T = 360 minutes) observed in preparations perfused with autologous blood (13,194 +/- 1942 dynes/sec/cm-5, T = 0; 24,768 +/- 3325 dynes/sec/cm-5, T = 360 minutes, p less than 0.05). We conclude that alteration of the cellular and humoral components of autologous blood may prove advantageous for increasing the utility of the autoperfused working heart-lung preparation as a preservation technique.

Total lymphoid irradiation and discordant cardiac xenografts

Total lymphoid irradiation can prolong concordant cardiac xenografts. The effects of total lymphoid irradiation in a discordant xenograft model (guinea pig to rat) were studied with and without adjuvant pharmacologic immunosuppression. Inbred Lewis rats were randomly allocated to one of four groups. Group 1 (n = 6) served as a control group and rats received no immunosuppression. Group 2 (n = 5) received triple-drug therapy that consisted of intraperitoneal azathioprine (2 mg/kg), cyclosporine (20 mg/kg), and methylprednisolone (1 mg/kg) for 1 week before transplantation. Group 3 animals (n = 5) received 15 Gy of total lymphoid irradiation in 12 divided doses over a 3-week period. Group 4 (n = 6) received both triple-drug therapy and total lymphoid irradiation as described for groups 2 and 3. Complement-dependent cytotoxicity assay was performed to determine if a correlation between complement-dependent cytotoxicity and rejection-free interval existed. Rejection was defined as cessation of graft pulsation and was confirmed by histologic test results. Only groups 1 and 2 showed a difference in survival (group 1, 6.9 +/- 1.0 minutes; group 2, 14.2 +/- 2.7 minutes, p = 0.02). Although total lymphoid irradiation did decrease complement-dependent cytotoxicity, linear regression revealed no correlation between complement-dependent cytotoxicity and graft survival (coefficient of correlation, 0.30). Unlike concordant cardiac xenografts, total lymphoid irradiation with or without triple-drug therapy does not prolong graft survival.

Clinical and hemodynamic performance of the Ionescu-Shiley valve in the small aortic root. Results in 117 patients with 17 and 19 mm valves

The Ionescu-Shiley pericardial valve was our bioprosthetic valve of choice between 1981 and 1985 for patients in whom the aortic anulus could not accept a valve larger than 19 mm in outer diameter or in whom the avoidance of warfarin sodium (Coumadin) was important. A series of 117 consecutive patients who received 17 or 19 mm valves for isolated aortic valve replacement or aortic valve replacement combined with coronary artery bypass grafting or other valvular procedures was analyzed. Overall, 74% of the patients were female, with a mean age of 70.9 years and a body surface area of 1.67 +/- 0.19 m2; 92.3% were in New York Heart Association class III-IV, and the operation was urgent or emergent in 46%. The operative mortality rate was 7.7%, with no deaths in patients undergoing isolated elective first-time aortic valve replacement. Mean follow-up for survivors was 2.5 years (10 to 62 months). There were 20 late deaths, of which three were valve related, three were due to sudden death or arrhythmias, and two were due to persistent heart failure. The actuarial survival rate at 5 years was 68%. Clinical follow-up revealed a low incidence of valve-related complications, and 96.4% of survivors were in class I-II. Postoperative echocardiography before hospital discharge revealed a maximum instantaneous gradient of 18.4 +/- 3.0 mm Hg in five patients having a 17 mm valve and 31.3 +/- 12.7 mm Hg in 20 patients having a 19 mm valve. Doppler echocardiography was performed in 22 patients at a mean follow-up of 39.3 +/- 11.7 months. The maximum instantaneous gradient was 25 +/- 17.2 mm Hg for 17 mm and 17.41 +/- 5.4 mm Hg for 19 mm valves at late follow-up. The effective orifice area was 0.85 +/- 0.1 cm2 for 17 mm and 1.21 +/- 0.21 cm2 for 19 mm valves. This study defines the normal range of Doppler echocardiographic transprosthetic gradients for the Ionescu-Shiley valve and confirms that low operative mortality and excellent clinical improvement can result from the use of small Ionescu-Shiley valves in elderly patients despite moderate postoperative transvalvular gradients.

Protective effects of retrograde compared with antegrade cardioplegia on right ventricular systolic and diastolic function during coronary bypass surgery

The effect of retrograde cardioplegia delivered through the right atrium on right ventricular performance has not been critically examined in humans. We randomized 20 patients with right coronary artery lesions to receive cold blood cardioplegia solution either retrograde through the right atrium (group 1, n = 10) or antegradely (group 2, n = 10). The patients were similar in age, sex, severity of coronary artery disease, cross-clamp time, and completeness of revascularization. Before operation, right ventricular function was assessed by radionuclide ventriculography, and 18-24 hours after operation, right ventricular volumes and performance were assessed at a constant-paced heart rate by simultaneous hemodynamic-radionuclide measurements, before and after a fluid challenge. Intraoperative right ventricular temperatures were not different between the groups. Right ventricular volumes and ejection fractions were not different at baseline. After operation, at similar heart rates and loading conditions, there was a trend for the antegrade group to increase right ventricular end-systolic volume (p less than 0.1) whereas the retrograde group had no change in this parameter from the preoperative state. Postoperative ventricular function curves (p = NS, retrograde versus antegrade) suggest equivalent systolic performance in both groups. Right ventricular diastolic performance showed no significant differences between the two groups, suggesting no detriment to compliance due to right ventricular distension during operation. This suggests that retrograde cardioplegia adequately protects the right ventricular myocardium during bypass surgery and may be used as an alternative procedure in situations where ventricular cooling is inadequate with antegrade delivery due to severe coronary artery disease or aortic valvular disease.

Transsternal radical thymectomy for myasthenia gravis: a 15-year review

Thymectomy is an accepted therapeutic modality for patients with myasthenia gravis. The selection of patients for operation and the surgical approach are controversial. We reviewed 52 patients (aged 18 months to 82 years; mean age, 34 years) treated with transsternal radical thymectomy between 1972 and 1987. Patients were symptomatically staged according to the modified Osserman classification. There was one hospital death and postoperative follow-up was obtained on 51 patients. Improvement after thymectomy was observed in 3 of 11 patients (27%) in Osserman stage I, 16 of 25 patients (64%) in Osserman stage IIA, and 13 of 15 patients (86%) in combined Osserman stages IIB, III, and IV. Preoperative Osserman stage, patient sex, and thymic histology correlated with postoperative clinical response. Transsternal radical thymectomy is effective therapy for myasthenia gravis. Sustained improvement is obtained in patients with moderate and advanced disease. The majority of patients with ocular disease do not benefit from operation.

Left ventricular inotropic effect of atrial pacing after coronary artery bypass grafting

The effect of atrial pacing on left ventricular (LV) performance was studied in 19 patients, 24 hours after coronary artery bypass grafting (CABG). LV volumes were calculated from simultaneous radionuclide-thermodilution measurements at rest (heart rate 82 +/- 12 beats/min), 10 minutes after the start of atrial pacing (100 beats/min), and with atrial pacing plus volume loading to return preload toward baseline. Atrial pacing reduced preload as reflected by LV end-diastolic volume index (69 +/- 14 vs 60 +/- 14 ml/m2, mean +/- standard deviation) (p less than 0.0001), but returned to baseline with volume loading. Afterload, as reflected by arterial end-systolic pressure, did not change with atrial pacing (63 +/- 9 at baseline vs 64 +/- 8 mm Hg with pacing, difference not significant). Afterload increased with volume loading (68 +/- 10 mm Hg, p less than 0.025 vs baseline and pacing). LV stroke volume decreased with atrial pacing due to reduced preload, but returned to baseline with volume loading. Cardiac index increased with atrial pacing and increased further with volume loading. Compared with baseline, LV end-systolic volume index was reduced during atrial pacing both before and after volume loading, despite unchanged or augmented afterload. The combination of atrial pacing and volume loading resulted in augmentation of LV stroke work, despite no increase in preload compared with baseline. Thus, after CABG, increased (paced) heart rate augments inotropic state, as indicated by reduced LV end-systolic volume under conditions of unchanged or increased afterload, and elevated LV stroke work without an increase in preload or a decrease in afterload.

Use of self-adhesive external defibrillator pads for complex cardiac surgical procedures

We describe a useful technique for the management of life-threatening arrhythmias that occur during complex or reoperative cardiac surgical procedures when internal defibrillation cannot be achieved. Two self-adhesive external pads are attached to the patient before draping to enable the delivery of current for defibrillation or cardioversion without the need for removal of adhesive surgical drapes and the cumbersome use of external defibrillator paddles.

Intravenous labetalol for the control of hypertension following repair of coarctation of the aorta

Paradoxical hypertension is a relatively common complication of surgical repair of coarctation of the aorta. An early phase of systolic hypertension has been ascribed to elevated levels of norepinephrine. Activation of the renin-angiotensin system from sympathetic stimulation has been implicated in a later phase of systolic and diastolic hypertension that can result in mesenteric arteritis. The use of a rapidly acting, titratable intravenous alpha- and beta-adrenergic blocker, such as labetalol hydrochloride, addresses both of these neurohormonal mechanisms. In the intravenous form, it would appear to be an excellent choice for the management of early postoperative hypertension and it can be converted to the oral form in cases of persistent hypertension. We report for the first time the use of labetalol in two young patients for the control of paradoxical hypertension following coarctation repair.

Successful repair of postoperative ascending aortic mycotic false aneurysms using circulatory arrest

Mediastinal wound infections following open-heart operations are successfully managed in most patients by aggressive debridement and placement of substernal drainage catheters or application of omental or muscle flaps. Nonetheless, the involvement of foreign bodies, such as felt pledgets adjacent to cardiac structures, can result in infections that persist despite flap coverage and can present as mycotic false aneurysms of the ascending aorta. We present the cases of 3 patients who underwent successful repair of such aneurysms late after surgical treatment of mediastinal wound infections. We describe our technique of repair using groin cannulation for bypass, moderate hypothermia, and circulatory arrest to improve exposure and minimize bleeding.

Cefamandole pharmacokinetics during standard and pulsatile cardiopulmonary bypass

The pharmacokinetics of cefamandole during standard or pulsatile cardiopulmonary bypass were studied in 13 adult cardiac surgery patients. All patients received 20 mg/kg of cefamandole intravenously at midnight before surgery, 6 AM on the morning of surgery and just prior to the initiation of cardiopulmonary bypass (CPB) surgery. Serum, skeletal muscle, and fat samples were taken at the beginning of CPB and at 30-minute intervals thereafter and assayed for cefamandole concentration. The average elimination rate constant and elimination half-life for cefamandole in patients undergoing standard CPB were 0.73 +/- 0.09 hour-1 and 0.94 +/- 0.11 hour, respectively. In contrast patients undergoing pulsatile CPB had significantly slower elimination rate constants (0.50 +/- 0.1 hour-1 and 1.4 +/- 0.28 hours, respectively; P less than or equal to .05). Area under the curve (AUC) values for cefamandole in fat and muscle tissue were higher in patients undergoing pulsatile CPB, but the differences were not statistically significant. Prolonged elimination from the serum, skeletal muscle, and adipose tissue, as compared with normal subjects, is seen with both pulsatile and standard CPB but is greater for the pulsatile method. Intraoperative dosing of cefamandole is required to maintain adequate serum and tissue levels for operations lasting longer than 4 or 6 hours in which standard or pulsatile CPB, respectively, are used.

Heterotopic heart transplantation: electrophysiologic changes during acute rejection

To identify electrophysiologic (EP) measurements sensitive to heart transplant rejection, heterotopic thoracic heart transplantation was performed in 11 dogs. Endocardial biopsies were performed daily for up to 9 days, and the severity of rejection was classified as mild, moderate, or severe. Late diastolic thresholds; refractory periods of the left ventricle and right atrium; and conduction times from the right atrium to left atrium, left ventricle to right ventricle, and right atrium to right ventricle were measured daily in transplanted and recipient hearts. The amplitude of the left atrium and right ventricular electrograms was recorded daily. In the recipient hearts no significant EP changes were observed after the second postoperative day. Left ventricular and right atrial refractory periods in both hearts did not change. In the transplanted hearts the conduction times of the right and left atria (but not the conduction time of the left to right ventricles) and right atrium to right ventricle identified moderate rejection; right atrial diastolic threshold was a marker only for severe rejection. Amplitudes of the left atrial and right ventricular electrograms decrease significantly only with severe rejection. At postmortem histologic evidence for rejection was greater in the atria than the ventricles. EP changes in the atria and atrioventricular conduction are more sensitive indicators of acute rejection than ventricular EP changes and correlate with the histologic grade of rejection. None of the measurements evaluated, however, was shown to be a sensitive marker of mild rejection.

Tracheoesophageal fistula associated with Barrett's ulcer: the importance of reflux control

A benign tracheoesophageal fistula occurring as a complication of Barrett's ulcerative esophagitis is described. Surgical control of gastroesophageal reflux resulted in healing of the fistula, obviating the need for a resective procedure or esophageal exclusion. Although Barrett's ulcer has been reported as a cause of acquired esophagorespiratory fistula, to our knowledge, the important role of reflux control in the management of this difficult problem has not been discussed.

Pericardiocentesis under two-dimensional echocardiographic guidance in loculated pericardial effusion

Pericardiocentesis to relieve tamponade from a loculated pericardial effusion in patients following cardiac surgery is greatly aided by two-dimensional echocardiographic imaging guidance. This technique delineates the fluid distribution and the site of adhesions, defines the path for introduction of an aspiration needle, alerts to the possibility of myocardial contact, and helps in positioning the drainage catheter. Two-dimensional echocardiographic imaging can be performed at the patient's bedside, and the images are easy to interpret. This technique simplifies pericardiocentesis and helps to avoid complications.

Vascular surgery in the United States. Report of the Joint Society for Vascular Surgery--International Society for Cardiovascular Surgery Committee on Vascular Surgical Manpower

The Joint Committee on Vascular Surgical Manpower was established in 1985 by the Society for Vascular Surgery and the North American Chapter of the International Society for Cardiovascular Surgery. It was charged to provide recommendations regarding vascular surgical manpower requirements for the next 15 years. Analysis of National Center for Health Statistics vascular operative rate data and 1690 questionnaire responses from vascular surgeons documented that vascular surgeons performed 235,400 (41%) of the total of 571,000 vascular operations undertaken in 1985. Vascular surgeons performed 87% of 30,000 aortoiliofemoral reconstructions, 77% of 72,000 peripheral vessel bypasses, 75% of 33,000 abdominal aortic aneurysm repairs, 59% of 55,000 angioaccess procedures, and 50% of 107,000 carotid endarterectomies. However, lack of accurate data on caseloads of surgeons who were not vascular specialists precludes precise prediction of manpower requirements for vascular surgery. It is important that surgical leaders and policy makers define the types of vascular surgical procedures that may be undertaken by vascular and other surgeons. Ongoing analyses must include such determinations to establish accurate data for the prediction of future manpower needs for vascular surgery. Furthermore, future manpower studies should be linked to outcome studies to assess not only numbers of surgeons and operations but quality of care as well.

Arterial bypass of the descending thoracic aorta with the BioMedicus centrifugal pump

Bypass of the descending thoracic aorta is frequently advocated as an adjunct for repair of traumatic tears and degenerative aneurysms. Many methods of bypass have been proposed to provide distal perfusion and reduce left ventricular afterload during cross-clamp of the thoracic aorta. We describe a simple method of direct arterial (aortoaortic or aortofemoral) bypass using the BioMedicus centrifugal pump with limited systemic heparinization.

Intraoperative, two-dimensional echocardiography-guided removal of retained intracardiac air

The removal of intracardiac air after cardiotomy may be simplified with the use of two-dimensional echocardiography. This technique can be used to readily identify retained pockets of air and can function as a guide to needle aspiration of the ventricular chambers. With a valve prosthesis in place, de-airing can be accomplished with minimal displacement of the heart. The technique is easy to use and the images are simple to interpret.

Cystic medial necrosis in coarctation of the aorta: a potential factor contributing to adverse consequences observed after percutaneous balloon angioplasty of coarctation sites

Percutaneous transluminal angioplasty has been shown to be both feasible and efficacious for the treatment of aortic coarctation. Recent reports, however, have indicated that the development of aortic aneurysms at or near the coarctation segment may complicate attempts to treat this lesion by catheter-based intervention. Accordingly, we examined the light microscopic features of coarctation segments excised at surgery (n = 31) or obtained at autopsy (n = 2) in 33 patients with coarctation of the aorta. Cystic medial necrosis, defined as depletion and disarray of elastic tissue, was observed in each of the 33 specimens. In the majority of coarctation specimens (22 of 33 or 67%) the extent of cystic medial necrosis, graded semiquantitatively on a scale of 0 (normal aorta) to 3+, was severe (3+). The finding that cystic medial necrosis represents a consistent histologic feature of coarctation of the aorta provides a pathologic basis for the formation of aneurysms observed after balloon angioplasty of coarctation sites.

Laser-assisted endocardiectomy for refractory ventricular tachyarrhythmias: preliminary intraoperative experience

Previous in vitro investigations utilizing necropsy specimens have suggested a potential role for laser irradiation in the treatment of refractory ventricular tachyarrhythmias associated with pathologically thickened endocardium. In the patient described in the present report, findings of these previous in vitro studies were applied intraoperatively to a patient undergoing surgery for ischemic heart disease associated with ventricular tachyarrhythmias. Aneurysm resection and manual subendocardial resection were performed using standard techniques. Laser irradiation was used to ablate pathologically thickened endocardium involving the papillary muscle and thereby avoid mitral valve replacement. Postoperatively, there was no auscultatory evidence of mitral regurgitation, and ventricular tachycardia could not be induced by electrophysiologic provocative testing. This preliminary experience confirms that laser irradiation is both a feasible and potentially advantageous means of accomplishing endocardial debridement in patients undergoing arrhythmia-ablation procedures.

Methemoglobinemia from intravenous nitroglycerin: a word of caution

The dose of intravenously administered nitroglycerin (IV NTG) used to control ischemic chest pain usually is limited by hypotension from decreased preload. Herein we describe 2 patients who tolerated IV NTG without hemodynamic compromise but in whom severe impairment of blood oxygen content developed from methemoglobinemia noted during coronary bypass surgery. Methemoglobinemia must be suspected if chocolate-brown blood is encountered despite a normal arterial oxygen tension and calculated oxygen saturation. Before a methemoglobin level is available, the extent of hypoxemia can be determined by an oximetric oxygen saturation and therapy begun with intravenous administration of methylene blue. These case reports focus attention on the potential deleterious effects of undetected hypoxemia from methemoglobinemia in patients being stabilized with high-dose IV NTG for urgent cardiac surgery.

In vitro analysis of mechanisms of balloon valvuloplasty of stenotic mitral valves

Preliminary reports indicate that percutaneous balloon valvuloplasty is efficacious for treatment of mitral stenosis. The present study was designed to evaluate whether anatomic features of stenotic mitral valves in older adults affect the efficacy of balloon valvuloplasty and to determine the mechanism by which increased orifice area is accomplished. Fifteen mitral valves excised intact at the time of mitral valve replacement from patients with no more than 2+/4+ mitral a regurgitation were selected for study. Balloon valvuloplasty was performed using a sequence of dilation catheters with balloons 18 to 25 mm in inflated diameter. Mitral valve area, measured with a conical valve sizer, increased from 0.71 +/- 0.06 cm2 (mean +/- standard error of the mean) to 1.77 +/- 0.19 cm2 (p less than 0.0001) after valvuloplasty, resulting in an increase in calculated orifice area of 185 +/- 27% (range 34 to 407%). The increase in calculated orifice area correlated inversely with orifice area before valvuloplasty (r = -0.57; p = 0.026), but was unrelated to extent of calcific deposits on the prevalvuloplasty x-ray of the excised mitral valve. Gross examination together with x-ray analysis after valvuloplasty revealed that the mechanism of balloon valvuloplasty in each case involved commissural splitting, including splits through heavily calcified commissures, without grossly apparent detachment of tissue fragments. These findings suggest that balloon valvuloplasty augments the functional mitral valve orifice area in a manner analogous to standard surgical commissurotomy, and balloon valvuloplasty is likely to be efficacious for a wide spectrum of adult mitral valvular stenosis, including severe stenosis with extensive calcific deposits.

Digoxin prophylaxis following coronary artery bypass surgery

The effect of the postoperative administration of digoxin to patients undergoing coronary artery bypass surgery on the incidence of supraventricular arrhythmias was studied. Patients were randomly assigned to a control group (n = 51) or digoxin group (n = 47) on a prospective basis. Patient characteristics were similar in both groups, and no patients were receiving digoxin therapy preoperatively or other antiarrhythmic medications. All patients had normal systolic ejection fractions, renal function, and hepatic function. Eight patients (16%) in the control group developed postoperative arrhythmias while seven patients (15%) in the digoxin group developed supraventricular arrhythmias. This difference was not significant. Two patients in the digoxin group developed digoxin-induced arrhythmias, and two other patients experienced digoxin-related nausea and vomiting, which were resolved with discontinuation of the drug. The postoperative administration of digoxin to patients undergoing coronary artery bypass surgery had no effect on the incidence of supraventricular arrhythmias. The prophylactic use of digoxin therapy in this patient population is not recommended unless there is a history of arrhythmias responsive to digoxin therapy.

Laser photoablation of pathological endocardium: in vitro findings suggesting a new approach to the surgical treatment of refractory arrhythmias and restrictive cardiomyopathy

In selected patients, malignant ventricular tachyarrhythmias have been successfully abolished by excision of subendocardial arrhythmogenic foci. Likewise, in certain patients in whom restrictive cardiomyopathy is due to endocardial thickening, endocardial resection has resulted in hemodynamic improvement. The present study was designed to explore the utility, in vitro, of laser photoablation of pathologically thickened endocardium. Endocardial photoablation was easily accomplished regardless of etiological or anatomical variations using either the focused beam of a carbon dioxide laser or argon laser light delivered through a 200-microns optical fiber. Photoablation of areas as large as 3.9 X 1.3 cm was performed within 40 seconds. The extent or depth of endocardial photoablation could be limited to 2 mm2 in area or 1 mm in depth using either form of laser therapy. These in vitro results suggest that either carbon dioxide or argon laser phototherapy can be successfully applied to the surgical treatment of refractory arrhythmias and restrictive cardiomyopathy. Advantages of laser photoablation include speed and precision. Furthermore, laser photoablation obviates the difficulty associated with conventional techniques in establishing tissue planes.

Digital subtraction angiography in patients with transposition of the great arteries after surgical repair

Digital subtraction angiography was used for postoperative evaluation of seven patients who underwent the Senning procedure for repair of d-transposition of the great arteries. Their ages ranged from 2.5 to 3 years. The patients were premedicated with methohexital (25 mg/kg rectally), and 0.3 to 0.4 ml/kg of diatrizoate was injected into a peripheral vein through a plastic needle. Images were obtained on a Technicare DR-960 or Diasonics DA 100 digital angiographic unit at four frames per second using 256 X 256 matrix and a 6 inch (15.24 cm) field size. In all patients, the venous systems, cardiac chambers and great arteries were well visualized. Two patients had obstruction of the superior vena cava with a dilated azygos vein draining into the inferior vena cava. One patient had severe obstruction of the left pulmonary artery. Digital subtraction angiography is safe and easy to perform and appears to be a valuable alternative method for evaluating patients after surgical repair of transposition of the great arteries. The small amount of contrast material required and the low radiation dose make it attractive for use in children.

Laser myoplasty for hypertrophic cardiomyopathy. In vitro experience in human postmortem hearts and in vivo experience in a canine model (transarterial) and human patient (intraoperative)

The feasibility of performing a myotomy/myectomy for hypertrophic cardiomyopathy (HC) by means of laser phototherapy was evaluated experimentally in vitro and in vivo, and the procedure then applied to a patient intraoperatively. In vitro experience revealed that the beam of an argon laser, delivered directly or via an optical fiber, could both cut and vaporize myocardium, producing a myotomy/myectomy morphologically similar to that produced by the conventional blade technique. In vivo experiments, in which the beam of an argon laser was delivered via an optical fiber to the ventricular septum of a canine heart, confirmed that a laser myoplasty could be achieved in 4 of 5 dogs by a transarterial approach. Finally, laser myoplasty was performed intraoperatively in a patient with HC, using a 200-mu fiber interfaced with an argon laser. Measured laser power was 1.5 W; cumulative exposure was less than 4 minutes; the myoplasty was 4 X 1 X 0.5 cm. These investigations establish the feasibility of using laser therapy to create a myoplasty trough that is similar in appearance to that typically achieved by the conventional blade technique. Illumination of the intraventricular operative field and precise modeling of the myoplasty trough constitute the principal advantages of laser myoplasty for HC.

Combined discrete subaortic stenosis and ventricular septal defect in infants and children

Eight patients, aged 1 to 8 years, with discrete subaortic stenosis (DSS) and ventricular septal defect (VSD) were studied by 2-dimensional (2-D) and M-mode echocardiography. Initial cardiac catheterization and angiocardiography showed VSD and other associated cardiac lesions, including coarctation of the aorta and patent ductus arteriosus. None had evidence of DSS. Six patients underwent surgical repair of the associated lesions, but none required closure of the VSD. Ultimately, 6 patients had spontaneous closure of VSD, and 2 had a residual small VSD. Subsequent serial echocardiography showed evidence of subaortic membrane, prompting repeat cardiac catheterization, which confirmed moderate to severe peak systolic pressure gradients between the left ventricle and ascending aorta. Surgical resection of the membrane was performed in 5 patients. Thus, in patients with small or spontaneously closed VSDs, DSS may develop. Evaluation of the left ventricular outflow tract area is recommended in patients with small or closed VSD in whom a significant heart murmur or electrocardiographic abnormality remains.

The impact of coronary artery disease on carotid endarterectomy

In a series of 531 CENDX, preoperative cardiac risk was categorized by clinical criteria. Patients with CAD (history of previous MI, angina, congestive heart failure, and/or electrocardiographic evidence of CAD were selected for more invasive studies based on clinical criteria. The overall incidence of postoperative myocardial infarction was 2.5% and increased slightly to 4% in patients with symptomatic cardiac disease. More importantly, the overall mortality was 0.9% and only 3 of 13 (23%) postoperative myocardial infarctions were fatal. Neurologic complications averaged 1.4% and approximately 70% were related to preceding cardiac events. Twenty-two patients or 4% of the entire series underwent carotid endarterectomy combined with coronary artery bypass graft and this approach was associated with one death and one stroke. Therefore, we conclude that a selective approach to coronary arteriography and subsequent CABG based on clinical criteria is associated with an acceptably low mortality and cardiac morbidity.

The third manpower study of thoracic surgery: 1980 report of the Ad Hoc Committee on Manpower of The American Association for Thoracic Surgery and The Society of Thoracic Surgeons

An ad hoc committee was appointed by The Society of Thoracic Surgeons (STS) in 1977 in order to determine the available manpower and workload of thoracic surgeons in 1976. This committee conducted a survey of the professional activities and geographic location of all known surgeons certified by the American Board of Thoracic Surgery (ABTS) at that time. A summary of this study indicated the available and projected thoracic surgery manpower. The report also determined the present and projected health care needs of the population of the United States through 1993. Because thoracic surgery needs to continue to meet the health care needs of the United States in an appropriate yet economical fashion, the STS and The American Association for Thoracic Surgery (AATS) undertook a joint review to determine again the available manpower and its workload in calendar year 1980. In addition, this study compared its findings with the 1976 report in order to detect changes in the workload and need for thoracic surgical services. A questionnaire was mailed to 3,584 certified thoracic surgeons. There were 2,675 responses. The material was sent to the Academic Computer Services at George Washington University Medical Center for tabulation and data processing. This report summarizes the results of this survey. It also compares these data with those obtained in the 1976 study and, based on this information, attempts to project the thoracic surgery manpower needs in the next decade by using several hypothetical models.

Atrial pacing during intraaortic balloon pumping

Intraaortic balloon pumping and atrial pacing are both useful in treating postoperative low output syndrome. However, the electrocardiographic atrial pacing spike can interfere with the electrocardiogram tracking mechanism of many balloon consoles. Bipolar epicardial pacing can avoid this problem and allow simultaneous atrial pacing and intraaortic balloon pumping.

Use of nitroprusside for control of pulmonary hypertension in repair of ventricular septal defect

After repair of ventricular septal defect (VSD) in a 3-year-old child with markedly elevated pulmonary vascular resistance (PVR), sodium nitroprusside was administered by intravenous infusion at 3.0 microgram per kilogram of body weight per minute. Nitroprusside was effective in reducing pulmonary artery pressure and increasing systemic blood pressure in the intraoperative and early post-operative periods. It is suggested that nitroprusside may facilitate the perioperative management and enhance the early survival in patients with increased PVR secondary to a VSD.