Edward S. Yee

Segmental mastectomy without radiotherapy short‐term follow‐up

Short‐term treatment failures following 43 segmental mastectomies without radiation therapy and 157 total mastectomies for primary operable breast cancer Stages I and II (T1–2, N0–1, MO) are compared. Although not randomized by design, the patients in the two treatment groups were of similar age and had tumors of comparable histologic type, size, grade, and stage. The overall recurrence rates in an average follow‐up of 24 months (range, 6–48 months) were 5% for patients treated by standard mastectomy and 19% for those treated by segmental mastectomy. Recurrence rates in patients with the more commonly encountered carcinomas of 11 to 50 mm in size treated by surgery alone were 7.5% for total mastectomy and 28.0% for segmental mastectomy. Nearly all of this difference relates to a higher frequency of local recurrence in the segmental mastectomy group (P = <0.005). Recurrent disease in both groups developed at comparable intervals, averaging 17 months for segmental mastectomy and 16 months for total mastectomy. Using a serial subgross technique, which permitted detection of clinically unsuspected involvement of resection margin by microscopic foci of carcinoma, it was noted that such involvement was an important prognostic indicator for local recurrence. Five of eleven breast resections with this feature developed local recurrence, compared with only 3 of 32 without such involvement of the resection margin. Cancer 52:2173‐2179, 1983.

Infant Coarctation: A Spectrum in Clinical Presentation and Treatment

Between 1975 and 1985, 125 infants 2 to 365 days old (majority, 30 days old or less) with coarctation of the aorta underwent surgical repair. Forty-seven patients (38%) had severe congestive heart failure (CHF), metabolic acidosis, and poor systemic perfusion. The predominant operative technique was synthetic patch aortoplasty (100 patients); the remaining 25 had an end-to-end anastomosis. There were no operative deaths. Perioperative complications were minimized with the synthetic patch technique (less than 15%). For patients surviving at least 3 months after repair, the arm-leg systolic blood pressure gradient was relieved in 82% (71/87) of the patients having patch aortoplasty versus 65% (15/23) of the patients with end-to-end anastomosis. Although the rate of reoperation between the two groups was similar (patch, 5 [6%]; end-to-end, 3 [13%], two of the reoperations in the patch group were for preexisting hypoplastic transverse aortic arch. Late deaths (20 patients, 16%) were due to other major associated cardiac anomalies. Patch aneurysms have not occurred. Expedient use of synthetic patch aortoplasty has decreased perioperative complications, relieved coarctation gradients for CHF, increased early survival even in the presence of complex or associated cardiac anomalies, and has an acceptable rate of recurrent coarctation (6 to 13%).

Tissue characterization by magnetic resonance imaging in hypertrophic cardiomyopathy

Abstract A method for providing tissue characterization of the myocardium has been sought for years. Magnetic resonance imaging (MRI) has demonstrated excellent soft tissue differentiation and has been proposed as a method for tissue characterization. This capability of MRI is suggested from previous studies that showed changes in signal intensity of ischemic compared with normal myocardium in experimental preparations. 1,2 Measurement of magnetic relaxation times, T1 and T2, in animal studies have verified a difference in these times between normal and ischemically damaged myocardium. 1–3 Recently, we encountered a patient with hypertrophic cardiomyopathy (HC) in whom MRI provided more accurate anatomic depiction of the condition than other imaging techniques. MRI also revealed differences in signal intensity at various sites in the left ventricular (LV) myocardium due to fibrosis and myocardial ischemia.

Determination of patch electrode position for the internal cardioverter-defibrillator by cine computed tomography and its relation to the defibrillation threshold

Cardioverter-defibrillator implantation in 22 consecutive patients after aborted sudden cardiac death was followed by prospective determination of the correct anatomic position of epicardial patch electrodes by chest X-ray study and cine computed tomography; the data were compared with the defibrillation threshold obtained intraoperatively. Patch electrode position was qualitatively graded. Computed tomography improved the assessment as compared with X-ray study in 13 patients (59%), visualizing electrodes in relation to the underlying myocardial and vascular structures. Although the computed tomographic technique provided more precise visualization, its grading of patch position correlated as poorly as that of the X-ray study with the measured acute defibrillation threshold. Three-dimensional reconstruction by computed tomography made it possible to determine quantitatively left ventricular mass (free wall and septum) and the mass encompassed by the patch electrodes. The 34.6 +/- 13.7% (range 12.6 to 61.1%) of the left ventricular mass encompassed by both patch electrodes showed a linear relation to the defibrillation threshold (r = 0.64, p = 0.01). Differentiation of free wall and septal mass in these measurements revealed that the proportion of septal mass encompassed by patch electrodes correlated closely with the defibrillation threshold (r = -0.6, p = 0.019), whereas that of the free wall mass, although significantly larger (35.4 +/- 15.8 vs. 20.6 +/- 15.4 g, p = 0.007), did not. Thus, the position of epicardial patch electrodes could be reliably determined by computed tomography.(ABSTRACT TRUNCATED AT 250 WORDS)

Intracoronary platelet aggregation: Pattern of deposition after ischemia, cardioplegia, and reperfusion

Platelet deposition in the coronary microvasculature has not been completely defined in the temporal relationship to acute myocardial ischemia, the application of crystalloid cardioplegia, and during reperfusion on heart bypass. Twenty-two canine hearts were serially biopsied for the analysis of radioactively tagged platelets. Eleven hearts underwent an isolated heart support preparation with seven followed by potassium cardioplegic arrest and reperfusion while the remaining 4 were maintained on continuous bypass. All 11 hearts undergoing bypass experienced transient (less than 90 sec) ischemia during bypass preparation and produced platelet aggregation in the myocardium (51.12 +/- 24.0 as compared to nonischemic control group 12.3 +/- 4.7; P = 0.005). Potassium cardioplegia did not completely wash out these platelets to the nonischemic control levels (27.8 +/- 14.9; P = 0.04). With the onset of reperfusion after 1 hr of cardioplegic arrest, platelet radioactivity profoundly increased (133.3 +/- 72.8; P = 0.0101) and remained high throughout the hour of reperfusion (324.7 +/- 269.3; P = 0.0369). In summary, intracoronary platelets are activated after transient ischemic episodes during initiation of heart bypass. These ischemia-activated platelet aggregations persist despite the application of cardioplegia during the arrest period. This deposition, in turn, allowed an ongoing pattern of platelet aggregation during the early and subsequent reperfusion. This pattern of ischemia-activated platelet aggregations probably accounts for the progressive reperfusion injury and support of an antiplatelet treatment for coronary microvasculature protection.

Accelerating HIV infection with cardiopulmonary bypass. Case reports

Five men patients and 1 woman patient who underwent either coronary artery bypass grafting (in 2) or valve replacement (in 3) or combined procedures (in 1) presented with severe HIV infection during the postoperative period. Four patients were NYHA Class III of IV with 3 patients in extremis requiring emergency procedures. All procedures were performed with cardiopulmonary bypass with mean time of 109 ± 48 minutes and aortic cross-clamp of 52 ± 49 minutes. Although the immediate postoperative courses seemed benign or uncomplicated, all presented with severe infections during the late postoperative period following their procedures (twenty-one to ninety days). The opportunistic infections were Pneumocystis carinii pneumonia (2), toxoplasmosis in the central nervous system and lung (1), cryptococcal meningitis (1), Staphylococcus aureus endocarditis (1), and viral encephalitis (1). Three died with two months of surgery. These complicated postoperative infections have raised the question of the safety of cardiopulmonary bypass in HIV-infected patients. Rational recommendations regarding preoperative HIV antibody testing, operative indications, and postoperative surveillance are offered.

Does prostacyclin (PGI2) cardioplegic infusion improve myocardial protection after ischemic arrest

To determine whether prostacyclin (PGI2) plays a beneficial role in the blood-perfused heart undergoing global ischemia, 20 isolated canine hearts were studied after sustaining one hour of cardioplegic arrest under moderate hypothermia (27 degrees to 28 degrees C). Left ventricular function (peak systolic pressure, rate of rise of left ventricular pressure [dP/dt], and compliance change in left ventricular volume), myocardial edema, coronary blood flow, and oxygen content were measured during the preischemic period and at 15 and 30 minutes during reperfusion. Results showed an improved hemodynamic recovery (peak systolic pressure, p = 0.018 at 30 minutes; dP/dt, p = 0.020 at 15 minutes) in the group of hearts treated with PGI2 infusion compared with controls. There was no difference in ventricular compliance or myocardial edema between the two groups. This benefit was attributed to a significant increase in myocardial blood flow (p = 0.028 at 15 minutes) and oxygen delivery (p = 0.021 at 15 minutes) during the reperfusion period with PGI2. These data suggest a potential clinical role for PGI2 when applied to the globally ischemic heart in the improvement of myocardial resuscitation during the early reperfusion period.

Reverse Saphenous Vein Homografts as Bypass Conduits: A Preliminary Report

Reverse saphenous vein homografts (RSVH) were needed in 16 patients during the past two years to offer a more thorough myocardial revascularization procedure since autogenous donor material was limited either because of previous surgeries or unuseable harvested conduits. All patients (11 men/5 women, mean age of 71.1 years) presented with severe coronary insufficiency. Nine patients were having reoperations after having previous successful operations (mean 6.9 years), and 2 were having third-time redo surgery about fifteen years after their initial procedures. RSVH were selected by ABO blood typing and were supported postoperatively by antiplatelet therapy. RSVH allowed additional bypass grafting in all patients and yielded an average of 4.1 grafts per patient. To minimize the operative risks, RSVH were mainly used for occluded targeted vessels or nondominant arteries. Three early deaths (less than thirty days) occurred from (1) progressive heart failure after emergent bypass and mitral valve repair for cardiogenic shock, (2) stroke after redo surgery, and (3) renal failure after urgent redo bypass. Although the mean follow-up was only 11.5 months, the remaining 13 patients have clinically improved. Five selected patients have been restudied with arteriography and have demonstrated successful revascularization, ie, patent internal mammary arteries (6/6) and autogenous venous grafts (5/5). However, 4/10 RSVH conduits were nonfunctional and the other 6 were patent. RSVH are effective conduits for cardiovascular reconstruction with excellent immediate hemodynamic characteristics similar to those of autogenous veins. They have been extremely effective in patients with limited autogenous donor material and, in selected cases, when a quick source of bypass material is needed in an emergent fashion. While the initial patency rates have been acceptable, long-term follow-up is needed for comparative rates.

Operative management of symptomatic MB

The relationships between coronary myocardial bridging (MB) and clinical symptoms have been controversial. Five young male patients underwent testing for symptomatic MB, manifested as angina with evidence of ischemia or sudden death. Preoperative testing included atrial stimulation studies for evidence of lactate extraction and serial cardiac catheterization. Positive lactate production and/or extensive milking (>90%) of the proximal left anerior descending artery (LAD) were documented in 4 patients, who were, therefore, treated surgically by supra-arterial myotomy. Associated intraoperative mapping and endocardial resection were required for significant anterior aneurysm and scars. Postopera tive studies demonstrated resolution of the milking and/or intracoronary gradi ents. The remaining patient had recurrent sudden death, but negative lactate study, and was treated by automatic internal cardiac defibrillator (AICD). Symptomatic young patients can present with pathologic compression of the proximal LAD from extensive MB. Complete supra-arterial myotomies were successful treatments. Other adjunctive surgical procedures: (1) mapping, (2) endocardial resection, and/or (3) AICD, were based on their preoperative stress testing and intraoperative findings.

A rapid microassay for myocardial ATPases

Abstract Current techniques for detection and assaying ATPase are cumbersome, inaccurate, compromising, whereas the modified coupled enzymatic assay for Mg +2 -dependent, Ca +2 -dependent, Ouabain-suppressible, and azide-inhibited ATPase is quick, reproducible, accurate, and truly measures maximal reaction rates. The assay allows these determinations on minute amounts of myocardiac tissue (as small as 18 mg), which in turn enables investigators to obtain paired biochemical and physiological data. The current assay design also allows simultaneous measurement of the various types of ATPases. This technique appears to be a useful part of biochemical armortorium in cardiac research.