Insulin resistance and liver histopathology in metabolically unhealthy subjects do not correlate with the hepatic abundance of NLRP3 inflammasome nor circulating IL-1β levels

INTRODUCTION

Systemic chronic low-grade inflammation has been linked to insulin resistance (IR) and non-alcoholic steatohepatitis (NASH). NOD-like receptor protein 3 (NLRP3) inflammasome and its final product, interleukin (IL)-1β, exert detrimental effects on insulin sensitivity and promote liver inflammation in murine models. Evidence linking hepatic NLRP3 inflammasome, systemic IR and NASH has been scarcely explored in humans. Herein, we correlated the hepatic abundance of NLRP3 inflammasome components and IR and NASH in humans.

RESEARCH DESIGN AND METHODS

Metabolically healthy (MH) (n=11) and metabolically unhealthy (MUH) (metabolic syndrome, n=21, and type 2 diabetes, n=14) subjects were recruited. Insulin sensitivity (homeostatic model assessment of IR (HOMA-IR) and Oral Glucose Sensitivity (OGIS₁₂₀)), glycemic (glycated hemoglobin), and lipid parameters were determined by standard methods. Plasma cytokines were quantified by Magpix. Hepatic NLRP3 inflammasome components were determined at the mRNA and protein levels by reverse transcription-quantitative PCR and western blot, respectively. Liver damage was assessed by histological analysis (Non-alcoholic Fatty Liver Disease Activity Score (NAS) and Steatosis, Inflammatory Activity, and Fibrosis (SAF) scores). IR and liver histopathology were correlated with NLRP3 inflammasome components as well as with liver and plasma IL-1β levels.

RESULTS

Body Mass Index, waist circumference, and arterial hypertension frequency were significantly higher in MUH subjects. These patients also had increased high-sensitivity C reactive protein levels compared with MH subjects. No differences in the plasma levels of IL-1β nor the hepatic content of Nlrp3, apoptosis-associated speck-like (Asc), Caspase-1, and IL-1β were detected between MUH and MH individuals. MUH subjects had significantly higher NAS and SAF scores, indicating more severe liver damage. However, histological severity did not correlate with the hepatic content of NLRP3 inflammasome components nor IL-1β levels.

CONCLUSION

Our results suggest that NLRP3 inflammasome activation is linked neither to IR nor to the inflammatory status of the liver in MUH patients.

[Removal of an infected gastric cyanoacrylate plug. Report of one case]

In patients with actively bleeding gastric varices, the treatment of choice is the endoscopic use of sclerosing agents such as cyanoacrylate. We report a 69-year-old man who, after being treated with cyanoacrylate, suffered from recurrent febrile episodes. After an extensive study and broad-spectrum antibiotic treatment, discarding other presumably infectious focus, the superinfection of the cyanoacrylate plug was suspected, and its surgical removal was decided. A partial gastrectomy of the gastric fundus, a splenectomy, and a distal pancreatectomy were performed. The patient evolved without fever and without new episodes of bacteremia, but with decompensation of his cirrhosis manifested by ascites, spontaneous bacterial peritonitis, pneumonia, and collections in the pancreatic bed. These complications were managed with medical treatment consisting in a long course of broad-spectrum antibiotics. Thereafter, the patient evolved satisfactorily.

Bariatric Surgery in Cirrhotic Patients: a Matched Case-Control Study

INTRODUCTION

Laparoscopic bariatric surgery (LBS) in liver end-stage organ disease has been proven to improve organ function and patients' symptoms. A series of LBS in patients with cirrhosis have shown good results in weight loss, but increased risk of complications. Current literature is based on clinical series. This paper aims to compare LBS (69% gastric bypass) between patients with cirrhosis and without cirrhosis.

METHODS

We conducted a retrospective 1:3 matched case-control study including bariatric patients with cirrhosis and without cirrhosis. Demographics, operative variables, postoperative complications, long-term weight loss, and comorbidity resolution were compared between groups.

RESULTS

Sixteen Child A patients were included in the patients with cirrhosis (PC) group and 48 in patients without cirrhosis (control) group. Mean age was 50 years; preoperative BMI was 39 ± 6.8 kg/m². Laparoscopic gastric bypass and laparoscopic sleeve gastrectomy were performed in 69% and 31%, respectively. Follow-up was 81% at 2 years for both groups. PC group had a higher rate of overall (31% vs. 6%; p < 0.05) and severe (Clavien-Dindo ≥ III; 13% vs. 0%; p = 0.013) complications than that of the control group. Mean %EWL of PC at 2 years of follow-up was 84.9%, without differences compared with that of the control group (83.1%). Comorbidity remission in PC was 14%, 50%, and 85% for hypertension, type 2 diabetes, and dyslipidemia, respectively. Patients without cirrhosis had a higher resolution rate of hypertension (65% vs. 14%, p = 0.03).

CONCLUSION

LBS is effective for weight loss and comorbidity resolution in patients with obesity and Child A liver cirrhosis. However, these results are accompanied by significantly increased risk of complications.

Breast lesions with atypia in percutaneous biopsies, managed with surgery in the last 10 years

Introduction

The optimal management of breast lesions with atypia (BLA), detected in percutaneous biopsies after screening mammograms, is a controversial issue. The aim of this paper is to compare histological diagnosis by percutaneous biopsy with the results of the surgical biopsy of these lesions and to analyse the changes to clinical approach this would imply.

Method

A retrospective study was carried out on patients operated on between June 2007 and June 2017 with a diagnosis of BLA. One hundred and forty-seven patients were identified with a pre-operative diagnosis of flat epithelial atypia (FEA), atypical ductal hyperplasia (ADH), atypical lobular hyperplasia, lobular carcinoma in situ and other atypia.

Results

The average age at diagnosis of BLAs was 52 ± 9.4 years. Radiologically, the lesions presented as microcalcifications in 79%, nodules in 15.6% and other lesions 5.4%. 73.5% of these were biopsied by means of digital stereotaxis. All of the patients analysed underwent a partial mastectomy. Changes in a biologically high-risk lesion were observed in 26.5% of the surgical specimens, of which 75.5% corresponded with ADH and FEA. In the percutaneous biopsies consistent with ADH (40.1%), ductal carcinoma was discovered in 6.8% (5.1% in situ and 1.7% invasive), which implied specific, multi-disciplinary management. Of the FEAs, 84.8% required a second treatment (surgery and/or hormone therapy ± radiotherapy, depending on whether it concerned FEA 59.6%, ADH 21.2% or ductal carcinoma in situ 3.8%).

Conclusion

These data show the clinical relevance in the diagnosis of ADH and FEA in percutaneous biopsies. For the diagnosis of FEA in particular, the associated risk of biologically high-risk lesions and ductal carcinoma is made evident.

Simultaneous TAPP inguinal repair and laparoscopic cholecystectomy: results of a case series

BACKGROUND

Cholecystectomy and inguinal hernioplasty are the most frequent surgeries in Chile and the world. Laparoscopic inguinal hernioplasty, being a clean surgery, reports mesh infection rates of less than 2% and adding a simultaneous laparoscopic cholecystectomy is controversial due to an increase in the risk of mesh infection. The aim of this paper is to report the results of simultaneous TAPP hernioplasty with laparoscopic cholecystectomy.

METHOD

Retrospective analysis of the digestive surgery database. We identified cases in which laparoscopic inguinal TAPP repair and simultaneous laparoscopic cholecystectomy were performed. Demographic, clinical information, hernia type and size, data from the surgery and its complications were also retrieved and analyzed.

RESULTS

We identified 21 patients, 86% male and with an average age of 61 years range 46-84. 72% of the hernias were unilateral, predominating indirect 50%, direct 28% and the remaining were femoral and mixed. The average hernia size was 2.2 cm. The meshes used were 56% polypropylene, 37% polyester and 5% PVDF. We report one gallblader perforation. At a median time of 40 months of follow-up (range 4-89 months), one hernia recurrence was found (3.7%), there were no reoperations at the time of the interview and there were no cases of mesh infection. Complications of surgery includes one ipsilateral testicular atrophy 4.8% and 1 ipsilateral inguinal seroma 4.8%.

CONCLUSIONS

In this series of cases, adding clean contaminated surgery to the inguinal TAPP hernioplasty was not associated with an increase in the infection of the mesh.

[Coronary reoperation: a 16 years retrospective analysis]

BACKGROUND

Coronary artery bypass grafting (CABG) reoperation is being performed with increasing frequency.

AIM

To assess the early and long term results of coronary reoperations in our institution and to identify prognostic factors.

PATIENTS AND METHODS

214 patients subjected to coronary reoperations between 1983 and 1999 were retrospectively studied.

RESULTS

Mean age was 64.2 years (range 42-79 years), 202 (94.4%) were male and 12 (5.6%) female. The mean interval between the operations was 125.7 months (range 6-252 months). 10 (4.6%) were emergency surgeries. Overall operative mortality was 5.6% (11 deaths) and in 5 patients (3.4%) a perioperative myocardial infarction was noted. Univariate analysis identified moderate or severe left ventricular failure (p = 0.048) as predictor of increased operative mortality, meanwhile age over 75 years (p = 0.02) and moderate or severe left ventricular failure (p = 0.01) were identified as predictors of increased in hospital mortality in the multivariate analysis. Follow up of in hospital survivors (mean interval 65 months, range 4 to 190 months) documented a 5 years survival rate of 82.9%, a 10 years survival rate of 73.1% and a 15 years survival rate of 53.4%. Moderate or severe left ventricular failure (p < 0.0001) and emergency surgeries (p = 0.007) were identified as factors influencing the late survival in the stepwise logistical regression analysis. Multivariate analysis identified left ventricular failure (p = 0.01) and peripheral vascular disease (p = 0.01) as predictors of decreased late survival.

CONCLUSIONS

Coronary reoperation has a low mortality in patients with a normal ventricular function and also has an excellent overall and disease free survival in the first 10 years of follow up. Left ventricular function is an independent risk factor increasing in hospital and late mortality.

[Myocardial revascularization of the anterior descending artery with the classical technic of mammary anastomosis]

INTRODUCTION AND OBJECTIVES

To establish the results obtained with the classical technique of mammary anastomosis of the anterior descending artery.

MATERIALS AND METHODS

Between January 1982 and July 1997, 154 patients received an anastomosis of the left internal mammary artery to the left anterior descending coronary artery with use of the classical technique (sternotomy and extracorporeal circulation).

RESULTS

There was no operative mortality in our group, nor paraoperational myocardial infarction, nor cephalic vascular accidents. One (0.6%) patient had sternal wound infection, and another (0.6%) required another reoperation for postoperational bleeding. All (100%) were followed-up from 3-183 months (average 64. 4 months). Actuarial global survival at 5, 10 and 15 years was 95.6%+/-2.1; 92.1%+/-4 and 85.5+/- 7.5 respectively, and the actuarial probability of being free from cardiac death was 99%+/-0.9; 99% and 99%. The actuarial probability of being free from myocardial infarction was 99%+/-0.9; 99%+/-0.9 and 99%; and from angina was 95%+/-2.2; 86.9%+/-4.9 and 74.5%+/-12.2 at 5, 10 and 15 years.Finally, the actuarial probability of being free from reoperation was 99%+/-0.9; 99%; 99% and from angioplasty 96.9%+/-1.7; 91.4%+/-4.1; 91.4%+/-4.1 at 5, 10 and 15 years, respectively. The average hospital charges in the last 10% of the patients was U$ 6.200.

CONCLUSIONS

Revascularization of the left anterior descending with the left internal mammary artery and the classical technique (sternotomy and extracorporeal circulation) is a safe, minimal risk, effective, long lasting and cost efficient procedure with excellent results at 10 and 15 years.

[Long-term results of reconstructive surgery for mitral insufficiency]

BACKGROUND

Surgical repair is the procedure of choice for mitral insufficiency since it preserves better left ventricular structure and function.

AIM

To assess the long term clinical and echocardiographic results of mitral valve reconstructive surgery.

MATERIAL AND METHODS

A review of clinical and echocardiographic data of 68 patients (34 male, age range 17 to 82 years), subjected to surgical mitral valve repair between December 1991 and March 1998. Preoperative functional capacity of these patients was 2.96 +/- 0.7. Surgical repair was assessed using transesophagic echocardiography in all subjects.

RESULTS

The etiology of mitral insufficiency was degenerative in 43 patients, rheumatic in 10, infectious in 6, ischemic in 5 and miscellaneous in 4. The most frequent pathological findings were dilatation of the mitral ring in 42% of patients, chordae tendinae rupture in 32% and enlargement in 24%. A mitral anuloplasty was done in 90% of patients, a cuadrilateral resection of posterior leaflet in 52% and chordae tendinae transference in 12%. An additional surgical procedure was done in 34% of subjects. Three patients died during hospitalization (4.4%). During the follow up of 36.5 +/- 22.3 months, five patients died and one required a mitral valve replacement. The actuarial survival probability was 95.3 +/- 2.6% at one year and 83.5 +/- 6.5% at five years. The reoperation free survival was 100% at one year and 97.4 +/- 2.5% at five years. At the end of follow up the functional capacity improved to 1.25 +/- 0.4. Echocardiography showed absence of mitral insufficiency in 48.4% of patients, minimal, mild and moderate insufficiency in 35.5, 14.5 and 1.6% of patients respectively.

CONCLUSIONS

Surgical valve reconstruction in mitral insufficiency has satisfactory long term results and should be the procedure of choice for eligible patients.

[Use of dual-chamber pacemaker. Short and long-term results]

BACKGROUND

Continuous improvement of dual chamber DDD pacemakers, electrode stability and programmed sequential stimulation changed the prognosis of patients implanted with these devices.

AIM

To report our experience with the use of dual chamber pacemakers.

MATERIAL AND METHODS

One hundred seventy six patients (116 male), aged 13 to 91 years old, who received a dual chamber pacemaker implant, are reported. Patients were followed for a mean of 2.6 years.

RESULTS

Indications for DDD pacemaker were complete atrioventricular block in 43%, sick sinus syndrome in 32%, paroxysmal A-V block in 24%. All pacemakers were Siemens-Pacesetter and were provided with an automatic sensing and threshold device. J shaped atrium electrodes were used in 78% of patients and screw-in electrodes in 22%. Post operative complications were displacement of atrial electrode in 8 patients, of ventricular electrode in 6 patients, infection in two patients and a hematoma in one. Chronic parameters, measured after six months, were within expected ranges and allowed a good reprogramming of pacemakers. Long term programming aimed to reduce battery depletion, enhance device performance and improve hemodynamic conditions. Normal sequential stimulation was achieved in 154 patients (87%), 14 (85) patients died of cardiovascular disease not related to pacemaker function. Eight patients were in atrial fibrillation and were reprogrammed to VVI and DDI modes.

CONCLUSIONS

DDD pacemakers are reliable and afford symptomatic relief in a broad spectrum of patients.

[Minimally invasive coronary artery surgery]

BACKGROUND

There is a growing interest to perform a left internal mammary artery (LIMA) graft to the left anterior descending coronary artery (LAD) on a beating heart through a minimally invasive access to the chest cavity.

AIM

To report the experience with minimally invasive coronary artery surgery.

PATIENTS AND METHODS

Analysis of 11 patients aged 48 to 79 years old with single vessel disease that, between 1996 and 1997, had a LIMA graft to the LAD performed through a minimally invasive left anterior mediastinotomy, without cardiopulmonary bypass. A 6 to 10 cm left parasternal incision was done. The LIMA to the LAD anastomosis was done after pharmacological heart rate and blood pressure control and a period of ischemic pre conditioning. Graft patency was confirmed intraoperatively by standard Doppler techniques. Patients were followed for a mean of 11.6 months (7-15 months).

RESULTS

All patients were extubated in the operating room and transferred out of the intensive care unit on the next morning. Seven patients were discharged on the third postoperative day. Duplex scanning confirmed graft patency in all patients before discharge; in two patients, it was confirmed additionally by arteriography. There was no hospital mortality, no perioperative myocardial infarction and no bleeding problems. After follow up, ten patients were free of angina, in functional class I and pleased with the surgical and cosmetic results. One patient developed atypical angina on the seventh postoperative month and a selective arteriography confirmed stenosis of the anastomosis. A successful angioplasty of the original LAD lesion was carried out.

CONCLUSIONS

A minimally invasive left anterior mediastinotomy is a good surgical access to perform a successful LIMA to LAD graft without cardiopulmonary bypass, allowing a shorter hospital stay and earlier postoperative recovery. However, a larger experience and a longer follow up is required to define its role in the treatment of coronary artery disease.

[Coronary surgery. 20 years of follow-up]

BACKGROUND

Since the first surgical coronary revascularization done in Chile in 1971, 5000 such procedures have been performed.

AIM

To assess the long term results of coronary revascularization surgery in our institution and to identify prognostic factors.

PATIENTS AND METHODS

Five groups of 100 patients each, composed by the first consecutive patients subjected exclusively to coronary bypass surgery in the years 1975, 1980, 1985, 1990 and 1995 were retrospectively studied.

RESULTS

Mean age of patients increased from a median of 52 years old in 1975 to 62 years old in 1995. No changes in the frequency of diabetes, hypertension, high serum cholesterol or previous myocardial infarction were observed. There was an increase in the proportion of patients with a recent (< 30 days) infarction that were operated along time. Seventy percent of patients had triple vessel disease or LMT and this proportion did not change. The number of grafts per patients increased form 1.9 to 3.4 and the use of arterial conduits from 0.18 to 0.81. Perioperative mortality remained constant and was 1.6%. Follow up information was obtained for 93% of 492 survivors. Actuarial survival at 5, 10, 15 and 20 years was 93 +/- 1, 82 +/- 2, 62 +/- 3 and 41 +/- 4% respectively. Ninety eight +/- 0.7, 89 +/- 2, 73 +/- 4 and 65 +/- 5% of patients remained free of a new myocardial infarction in the same lapses, respectively. Ninety seven +/- 1, 94 +/- 2, 76 +/- 4 and 47 +/- 7% of patients remained free of a new operation. Stepwise logistical regression analysis identified as bad prognostic factors, in decreasing order: cardiac failure, diabetes, smoking, hypercholesterolemia and age at the moment of operation.

CONCLUSIONS

Coronary artery bypass surgery provides good and long lasting clinical improvement. The prognosis of patients is influenced by the presence of cardiac failure, some well known coronary risk factors and age at the moment of operation.

[Myocardial revascularization with one and two mammary arteries: clinical results and long-term follow-up]

BACKGROUND

Coronary bypass grafts made with internal mammary artery have better long-term results than those made with saphenous vein. It is possible that the use of both mammary arteries would lead to even better results.

AIM

To compare the long-term survival and the incidence of new coronary events of patients, in whom one or two mammary arteries were used as coronary bypass grafts.

PATIENTS AND METHODS

One hundred and eight randomly selected patients who received one mammary artery for myocardial revascularization and 108 patients, matched for prognostic factors, who received two mammary arteries were studied. These patients were followed for a mean of 4 years (range 1 to 12 years). Operative complications, hospital mortality and long-term probability of being free of disease were compared in both groups.

RESULTS

Operative mortality was similar in both groups (0.9%). Patients that received two mammary arteries had a higher frequency of operative wound complications. Long-term survival was 84% in patients who received one and 83% in patients who received two mammary arteries. The probabilities of being free of myocardial infarction (92 and 82% respectively) and angina (94 and 86% respectively) were lower in the later group.

CONCLUSIONS

Patients who received two mammary arteries had a higher probability of a long term disease free survival than patients who received one mammary artery.

[Carotid endarterectomy combined with myocardial revascularization: report of 27 patients]

Atherosclerosis is a systemic disease that may involve more than one territory. Myocardial infarction can occur after carotid endarterectomy and stroke is a well documented morbidity of coronary artery bypass grafting. To optimize results, we have performed concomitant carotid endarterectomy and myocardial revascularization in selected cases, with severe disease in both territories. During a 13-year period, 27 patients were submitted for this procedure, 21 (77.8%) were male and the average age was 67.6 years (range 59-81). All patients had high-grade internal carotid artery stenosis, five (18.5%) were symptomatic. Coronary artery disease symptoms were: unstable angina in 12 patients (44.4%) and effort angina in 15 (55.6%). Two patients (7.4%) required reintervention for postoperative bleeding. Two cases (7.4%) had transient renal dysfunction. One patient, with multiple organ failure, died on the 16th postoperative day (3.7%). Follow up was obtained in 26 patients (96.3%). Survival at 5 years was 80.6%, 95.7% of those patients were free of any neurologic symptom. Combined carotid and coronary surgery is a safe treatment option for atherosclerosis of multiple territories in selected patients; long term benefits are also obtained.

[Pulmonary thromboendarterectomy: a case of surgical treatment of chronic pulmonary thromboembolism under circulatory arrest with deep hypothermia]

Pulmonary thromboendarterectomy under circulatory arrest and deep hypothermia is presently a curative treatment for pulmonary hypertension secondary to chronic pulmonary artery thromboembolic occlusion, but is still not frequently performed around the world. We report here the first successful pulmonary thromboendarterectomy under circulatory arrest performed in Chile. The patient was a 37 year old white man, high school teacher, with a 5 months history of effort dyspnea and cough. Pulmonary hypertension secondary to chronic pulmonary thromboembolism was confirmed by angiography and echocardiography. The patient was operated on April 27, 1995. After the operation the patient had an immediate and maintained normalization of his pulmonary hemodynamics. He presented periods of delirium that postponed mechanical ventilation disconnection until the 7th postoperative day, after which he had an uneventful neurological recovery. Before hospital discharge a control angiography showed complete patency of the pulmonary artery system with no evidence of residual thrombi. Presently he is enjoying a normal life and back to his teaching activities.

[Surgical myocardial revascularization during the 1st 15 days of evolution of acute myocardial infarction]

Revascularization significantly improves early and late prognosis in acute myocardial infarction and has prompted substantial changes in therapeutic stategies. We report 140 patients aged 60.3 years old (123 male) operated within 15 days of sustaining an acute myocardial infarction, between January 1984 and December 1989. Coronary angiogram showed single vessel disease in 8 (6%), double vessel disease in 32 (23%), triple vessel disease in 85 (61%) and left main vessel disease in 13 (9%). Indications for surgery were postinfarction angina in 92 patients (66%), multiple severe coronary stenoses in 18 (13%), infarction of less than six hours from onset in 16 (11%), acute angioplasty failure in 7 (5%) and cardiogenic shock in 7 (5%). Thirty one patients were operated during the initial 24 h of infarction (16 with less than 6 h), 14 between the second and third day and 95 between the fourth and fifteenth day. Overall mortality was 4.3% (6/140). Among patients with failed angioplasty and cardiogenic shock, mortality was 23% (7/140), among patients with postinfarction angina this figure was 2.1% (2/92). No patient operated within 6 hours of infarction onset or due to severe coronary stenosis, died. Ninety seven percent of patients were followed during mean of 49 months. Three patients had a new acute myocardial infarction, two had sudden death and two died of unrelated causes. One required angioplasty and none was reoperated. Five years actuarial survival was 95% and the actuarial probability of being free of acute myocardial infarction, angioplasty or reoperation at five years was 99 and 100% respectively. It is concluded that early surgical revascularization in cute myocardial infarction is safe and has excellent long term results.

[Papillary muscle rupture in myocardial infarction]

We report nine patients with acute mitral regurgitation secondary to post-infarction papillary rupture operated between 1980 and 1992. Seven cases had posterior papillary muscle rupture. All patients were in critical conditions with pulmonary edema at the moment of surgery. In eight cases, mitral valve replacement was performed (4 with mechanical prostheses) and in one, the valve was repaired with papillary muscle reimplantation. Six cases were also subjected to myocardial revascularization with sapheneous vein grafts. Two patients (22%) died during the postoperative period and 4 had postoperative complications. The seven survivors have been followed during 6 to 115 month. Of theses, one died six month after surgery due to congestive heart failure, three are in functional class I and the rest in functional class II. It is concluded that, although mitral valve replacement for papillary muscle rupture has a high operative mortality and morbidity, long term results are satisfactory.

[Surgery of acute mitral valve insufficiency]

Between January 1980 and December 1990, 16 patients with acute mitral insufficiency were operated on an emergency basis at our institution. They represented 1.8% of all mitral surgical cases. All of them were in acute pulmonary edema and 7 in cardiogenic shock. The etiology was ischemic in 6, degenerative in 4, infectious in 3, degenerative and infectious in 2 and traumatic in 1. The pathologic mechanism was chordal rupture in 8 patients (5 anterior) and papillary muscle rupture in the other 8 (5 posterior). A mitral valve replacement was performed in all cases. Two patients died and 7 had morbidity in the postoperative period. One patient died 6 months after surgery of congestive heart failure. Ten patients are in NYHA functional class I at a mean follow-up of 48.1 months. Acute mitral insufficiency has different etiologies and pathologic mechanisms. In spite of the severe clinical condition of these patients, mitral valve replacement has good immediate and long-term results.

[Dissection of the ascending aorta (type A): diagnostic aspects, surgical treatment and long-term follow-up]

Aortic replacement is the treatment of choice and improves the natural history of dissections involving the ascending aorta. Forty patients (23 male), aged 49.4 years, have been operated at the hospital Clínico de la Universidad Católica. Twenty six presented with acute dissections. Angiography conformed the dissection in 63.3% and computed axial tomography in 84.6% of patients; lately, transesophageal echocardiography has become the most sensitive diagnostic method. Twenty three patients (57.5%) were subjected to emergency operations and 17 to semielective procedures. In 24 patients (60%) ascending aorta was replaced and in 16 a composite graft was used. Operative mortality was 27.5%. Univariate analysis showed that the period in which the operation was performed and the presence of limb ischemia were the only independent predictors of operative mortality. Long term follow up was achieved in 26 patients (89.6%). Actuarial 5 year survival without considering operative mortality was 87.9%. It is concluded that patients with acute dissections involving the ascending aorta should be operated as soon as the imaging diagnosis is complete and, since this is a palliative procedure, a close follow up is required for early detection of complications.

[Interventricular rupture following myocardial infarction. Surgical treatment and long-term follow-up]

The natural course of post myocardial infarction ventricular septal defect is towards cardiogenic shock and death. 50% in the first week, over 90% a year latter. Between 1973-1989, 28 patients where operated on. Before surgery 14 patients (53%) where in Killip IV, 5 patients (19%) in III, 5 patients (19%) in II and 2 patients in I. The repair was accomplished under hypothermia and cardioplegia, with the insertion of a Teflon patch to close the defect in 20 patients (70%). Complementary procedures (CABG, Pacemaker, repair of dissections) were performed in 12 patients (47%). Three patients (10%) could not be weaned from the pump; another 10 (36%) died before discharge: 2 with multisystem failure and sepsis, the other 8 with cardiogenic shock (4 with residual VSD). The only independent predictor of operative mortality, by univariate analysis, was preoperatory cardiogenic shock. All 15 survivors (100%) where followed between 5 months and 14.5 years (mean 104.5 months). Two patients died at 4 years, one at 10, another at 10.5 years. The actuarial probability of being alive after discharge was 100% at 4 years, 75% at 5, and 50% at 10 years. At last follow up only 2 patients had mild dyspnea, the remaining where asymptomatic. Surgical treatment provides an opportunity to improve this otherwise dismal survival and offers a surprising good long term result. An early diagnosis and efficient repair, before the onset of cardiogenic shock, should provide better results.

[Radiotherapy in the treatment of non-small-cell lung cancer]

The results of curative radiotherapy in 59 patients with non-small-cell carcinoma of the lung treated from 1977 to 1988 are reported. Squamous cell carcinoma without evidence of metastatic disease was present in 28 patients. Radiotherapy alone was used in 43 patients; 13 patients received either pre or post operative radiotherapy. Complications developed in 6 patients, only 1 had esophageal stenosis deemed important. The first site of failure was extrathoracic in 76% of patients, the brain being the most frequently involved site (41%). Brain failure rate was greater for squamous cell carcinoma than for other tumors. The 5 year survival rate was 20% with a minimum follow up period of 24 months (median 57). Better results were obtained in patients receiving high dose continuous radiotherapy and in those with associated surgery. Thus, radiotherapy is an alternative therapy for patients with lung carcinoma, with a reasonable survival rate and few complications.

[The long-term evolution of aortic valve replacement with a mechanical prosthesis: experience with the Starr-Edwards (1965-1974) and Bjork-Shiley (1973-1981) prostheses]

We compared the short- and long-term results of isolated aortic valve replacement in 98 patients receiving a Starr-Edwards (SE) prosthesis from 1965 to 1974 and 80 pts receiving a Bjork-Shiley (BS) prosthesis from 1973 to 1981 at our institution. Operative mortality was 20% (SE) and 6% (BS). Follow-up information was obtained in 88% (SE) and 96% (BS) of pts discharged alive. The mean period of follow up was 8.2 and 6.7 years respectively. The 5 and 10 year actuarial survival rates were 72% and 61% (SE) vs 89% and 83% (BS). Complications per 100 pt-years among pts with SE and those with BS were: systemic emboli 2.8 vs 0.6, major hemorrhagic events 1.25 vs 1.36, perivalvular leak 1.6 vs 1.15, endocarditis 0.31 vs. 0.39, prosthetic thrombosis 0 vs 0.58 and ball variance 0.47 vs 0, respectively. Some of these differences may reflect shortcomings of the initial surgical experience during the period in which the SE prosthesis was used, rather than different performance of both valves.

[Wolff-Parkinson-White syndrome: late results of surgical treatment]

We followed 25 patients operated on for Wolff-Parkinson-White syndrome between August 1985 and October 1989. Their mean age was 37 +/- 12 years and arrhythmia had been present for 5 to 30 years. A mean of 3.3 +/- 1.2 antiarrhythmic agents had failed in controlling recurrences. Tachycardia was orthodromic in 21 patients and antidromic in 1, while 3 patients presented rapid atrial fibrillation with hemodynamic deterioration. Drug refractoriness (n = 23) or intolerance (n = 2) were the main surgical indications. The location of accessory pathways was lateral in 19 patients, anteroseptal in 3, posteroseptal in 2, postero lateral in 1 and right lateral in 1 patient. One patient had a double pathway. There was no surgical mortality. After a follow-up period ranging from 1 to 50 months recurrence of arrhythmia was observed in one patient and electrophysiologic evaluation showed persistence of a left lateral pathway in another. The remaining 24 patients are free of symptoms at the end of follow up. Thus, surgical treatment is a curative therapy for most patients with WPW.

[Surgery of evolving myocardial infarction]

Limitation of infarct size has been proven to improve the prognosis in patients with recent myocardial infarction (MI). Emergency coronary bypass surgery may be used for this aim. We operated on 44 such patients within 15 days of onset of MI. Operation was done within 6 hr in 11 patients and later on in the other 33, due to post infarction angina or incomplete MI. One patient died in the perioperative period. Thirty nine patients were followed at a mean of 33 months: 2 have angina, one dyspnea and the rest is asymptomatic. We believe that bypass surgery is an effective treatment in selected patients with recent MI.

Disc dislodgment in Björk Shiley mitral valve prosthesis: two successfully operated cases

Two patients with Björk Shiley mitral valve replacement had migration and embolization of the occluding disc. One patient suffered migration of the disc a few hours after surgery and the other had a strut fracture with disc translocation six years after the initial operation. Clinical signs in both cases were pulmonary edema, cardiogenic shock, and absence of prosthetic sounds. Both patients were reoperated on an emergency basis, recovering after a complicated postoperative course. They are on functional Class I, 8 and 1 years later, respectively, with their dislodged discs still in the abdominal aorta. The only hope for survival in these patients is emergency reoperation, once the prosthetic mitral valve dysfunction is confirmed.

Ultrastructural myocardial preservation during coronary artery surgery: a controlled, prospective, randomized study in humans

Potassium cardioplegia was compared with normothermic, intermittent ischemic arrest in 30 patients undergoing multiple coronary artery bypass grafts. Group 1 comprised 15 patients in whom cold potassium cardioplegia with St. Thomas' Hospital solution was used. In Group 2 were 15 patients who underwent intermittent ischemic arrest during the construction of the distal anastomoses. Two myocardial transmural left ventricular biopsies were done in each patient. There was no operative mortality. Electron microscopical examination showed normal myocardial ultrastructure in both groups. In particular, mitochondria were well preserved in all samples. The postoperative electrocardiogram demonstrated a new Q wave in 1 patient in Group 2 whose level of the myocardial isoenzyme of creatine phosphokinase (CPK-MB) was within the normal range. The peak CPK-MB release in Group 1 was 23.2 +/- 20.1 IU and in Group 2, 19.9 +/- 15.1 IU. This difference was not statistically significant. The mean period of anoxic arrest in Group 1 was 49.5 +/- 15 minutes and in Group 2, 25.5 +/- 8 minutes (p less than 0.001). Total cardiopulmonary bypass time in Group 1 was 114.5 +/- 20 minutes and in Group 2, 90.2 +/- 16 minutes (p less than 0.01). It is concluded that both techniques can preserve myocardial subcellular architecture during multiple coronary artery bypass grafting in patients with normal left ventricular function.

Surgical removal of entrapped endocardial leads without using extracorporeal circulation

Of 267 patients having a tined endocardial lead implanted from 1978 to December 1983, three (1.1%) developed pulse generator pocket infection. Proper treatment of this complication involves removal of the pulse generator, continued external pacing via the implanted lead, pocket drainage and administration of specific antibiotics until the infected area clears. In two patients, the electrode could not be removed by traction. A sternotomy was performed, the pericardium was opened, the endocardial electrode was located by palpation, and a purse string suture (PSS) was prepared around it on the right ventricular wall. A new myocardial electrode with its corresponding generator was then implanted to reestablish pacing. Through the PSS the myocardium was incised, the distal end of the endocardial lead was exteriorized and severed, and the PSS was tied. The remaining lead was withdrawn proximally and the surgical wounds were closed. The results of this procedure have been been excellent, allowing the removal of the entrapped leads, with continuous pacing and without the need for extracorporeal circulation.

[Atrial myxoma. Report of eight surgical cases, four with electron microscopy study (author's transl)]

From 1970 to 1979 we studied and operated on 8 patients with atrial myxoma, 7 females and 1 male, 24 to 58 years of age. Symptoms had been present for 4 to 24 months prior to surgery. Five patients were functional class IV (NYHA), 2 class III and one class I. All patients were studied by catheterization and angiography. The diagnosis was suspected from physical findings in 3 patients and was not made before surgery in 2 cases. The tumor was located at the left atrium in 6 patients and the right atrium in 2. Electron microscopy performed in 4 cases revealed the typical findings of myxomatous tissue. Adequate resection under extracorporeal circulation was possible in all subjects. One female who was in severe congestive heart failure died shortly after operation. The survivors did well, remaining functional class I, one to nine years after surgery.

Preoperative estimation of risk in cardiac surgery

In order to determine the usefulness of the preoperative subjective estimation of risk and compare it with preoperative estimation of risk based upon objective data, two groups of patients subjected to open heart surgery at the Catholic University of Chile Hospital were studied prospectively. Group I comprised 227 consecutive patients operated on in 1975 and group II comprised 181 consecutive patients operated on in 1979. There were several important differences in management and techniques between the two groups, which resulted in different factors perioperative mortality. Mortality in group I was related to extreme age subsets (p less than 0.01) and to duration an anoxic arrest (p less than 0.001); mortality in group II correlated only to preoperative functional class (NYHA) (p less than 0.02). Despite these differences, subjective risk estimation as preoperatively recorded by the anesthesiologist was accurate in both groups (r = 0.969, p less than 0.05 in group I and r = 0.998, p less than 0.01 in group II). It was concluded that in the absence of a universally valid objective risk index, subjective risk estimation provides a clinical index as useful as reliance upon presently available objective data.

Bloodless cardiac surgery utilizing a new low-prime oxygenator

One hundred consecutive patients undergoing open-heart surgery were subjected to a prospective protocol designed for reduction of homologous blood utilization. The main points of this protocol were careful surgical hemostasis, normovolemic hemodilution, and retransfusion of blood lost to the operating field. It included use of the new Bentley BOS-10 Spiraflo oxygenator (Bentley Laboratories, Inc., Irvine, California, U.S.A.). The patients' ages ranged from 6 to 68 years and their weights from 18 to 84 kg. Fifty-four patients were subjected to valvular surgery, 30 to coronary revascularization, 13 to congenital defects repair, and 3 to resection of atrial myxomas. All patients could be weaned from bypass without receiving any blood. Eighty patients completed their surgery, and 60 were discharged from the intensive care unit without receiving any homologous blood or its derivatives. Total blood usage for the series throughout the entire stay in hospital was 1.32 units/patient, which included six reoperations for excessive bleeding. This reduction in blood utilization was achieved without excessive hemodilution and did not produce significant complications.

Elective correction of intracardiac lesions resulting from penetrating wounds of the heart

Controversy exists regarding the timing and technique of total correction of traumatic intracardiac lesions. Five patients with penetrating wounds of the heart received emergency treatment aimed at securing normal haemodynamics. No attempt was made to identify intracardiac lesions at this stage. Cineangiography two months to seven years later showed aorto-right ventricular fistulae in all patients, associated in two with aortic cusp laceration and in one with an aorto-left atrial fistula. The surgical approach for aorto-right ventricular fistula was through the right ventricle or aorta. Valvar injuries were treated by plastic reconstruction. All patients showed good clinical results when seen four to 11 years later. Traumatic intracardiac lesions in patients with stable haemodynamics after initial treatment should be operated on electively. The aortic approach is preferable for aorto-right ventricular fistulae. Conservative plastic repair of valvar injuries achieves long-term competence thus avoiding prosthetic replacement.

[Coronary occlusions associated with chronic arsenic poisoning. Apropos of 2 operated cases]

Examination was made of the clinical history, the results of laboratory tests, of coronary arteriography, and of a histological study of the coronary arterial walls in two young men who had a myocardial infarction. The two men lived in a district where the drinking water had a very high level of arsenic (0.8 parts per million). Neither of the patients presented the risk factors which are usually associated with coronary arteriosclerosis. Neither of the patients presented the risk factors which are usually associated with coronary arteriosclerosis. A histological study of the pathological left ventricular wall, which was removed at operation, showed very characteristic features of fibrous thickening of the intima, with preservation of the internal elastic lamina, of the medial and of the adventitia. Such an arterial abnormality may effect the larger coronary arteries just as well as the medium and small ones. Clinical presentation of this condition is often in young subjects.

Spontaneous rupture of a fenestrated aortic valve. Surgical treatment

Fenestration of the aortic valve is a common anatomic finding. Although spontaneous rupture of the semilunar cusps is infrequent, it leads to rapidly progressive heart failure and death. We present, to our knowledge, the first case of successful treatment by valve reconstruction. A 2 year follow-up demonstrates excellent clinical results.

Cardiovascular management of pregnant women with a heart valve prosthesis

This study of 14 pregnancies in 11 patients with a Starr-Edwards valve prosthesis (nine mitral, two aortic) shows that cardiac functional capacity deteriorated to class III (New York Heart Association criteria) in only 1 woman. The deterioration occurred during the third trimester and the patient's condition improved with medical therapy. Careful medical control diminished the incidence of heart failure in these patients. Six of nine pregnant women with a mitral valve prosthesis were treated continuously with coumarin and three discontinued the therapy gradually before the third trimester of pregnancy. In five pregnant women (three with an aortic valve prosthesis, two with a mitral valve prosthesis) no anticoagulant agents were used. No embolic episodes or severe hemorrhagic complications were seen. One newborn whose mother received coumarin during the first trimester had bilateral hand polydactylia. There were no maternal deaths. One neonate died after fetal stress necessitating the only cesarean section. These results suggest that women with an artificial heart valve tolerate pregnancy well and that anticoagulant therapy is not mandatory in pregnant women with an aortic valve prosthesis, or in the few women with a mitral valve prosthesis not already receiving coumarin at the onset of pregnancy.