Makoto Yamada

Surgical lead-preserving procedures for pacemaker pocket infection

BACKGROUND In the treatment of pacemaker pocket infection, removal of the entire pacing system has been considered necessary to avoid recurrent infection. We report a series of patients treated surgically by our lead-preserving procedures. METHODS Between 1990 and 2001, a total of 18 patients underwent one of two types of lead-preserving procedures. Procedure 1 preserves the full length of the lead, and procedure 2 preserves only the distal part of the lead. Signs of bacteremia, endocarditis, or purulent material within the lead insulation preclude application of these procedures in patients with potential or definite pacemaker pocket infection. RESULTS Seventeen patients who met the indications for our procedures were discharged 7 to 14 days (8.9 +/- 2.4 days, mean +/- SD) postoperatively without signs of infection and were followed up for a total of 987 patient-months until the close of the study or death without recurrent infection. The remaining 1 patient, who did not meet the indications, suffered reinfection soon after the operation. CONCLUSIONS The follow-up data suggest that our lead-preserving procedures should be considered as alternatives to conventional removal of the entire pacing system in cases of pocket infection that meet specific criteria.

Atrophy of the abdominal wall muscles after extraperitoneal approach to the aorta

OBJECTIVE We retrospectively assessed computed tomography (CT) scans to determine degree of anterolateral abdominal muscle atrophy in patients who underwent infrarenal aortic repair with 2 kinds of incisions for the extraperitoneal approach. METHODS CT scans obtained before surgery and final scans obtained 2 to 100 months after surgery were assessed in 12 patients with paramedian incision (PM group) and 27 patients with flank incision (F group) who could be followed up at our hospital. We considered muscle thickness before surgery on the incision side to be 100% thickness (baseline value), and we calculated, by measuring the incision side after surgery, the corrected percent thickness (CPT%), which represents percentage of remaining muscle thickness that has escaped incision-induced atrophy. CT scans obtained at the level of the third (L3) and fifth (L5) lumbar vertebrae and the center of the sacrum (S) were selected for CPT% measurement. RESULTS Duration from surgery to final CT scan was 2 to 65 months (mean +/- SD, 34.33 +/- 21.38 months) in PM group and 3 to 96 months (27.85 +/- 20.74 months) in F group. In PM group, mean CPT% values of the rectus abdominis muscle were 55.83 +/- 21.65% at L3, 35.50 +/- 10.79% at L5, and 31.92 +/- 11.00% at S; these values were statistically much smaller than baseline (P <.01). Mean CPT% values of the lateral abdominal muscles were not statistically different from baseline. In F group, mean CPT% values of the rectus abdominis muscle were 82.19 +/- 23.15% at L5 and 64.41 +/- 31.34% at S; these values were statistically smaller than baseline (P <.01). Mean CPT% values of the lateral abdominal muscles were 87.59 +/- 22.30% at L3 and 84.59 +/- 26.90% at L5; these values were statistically smaller than baseline (P <.05). CONCLUSIONS Paramedian incision induced severe rectus abdominis muscle atrophy. Although flank incision induced various degrees of atrophy in both muscles, some patients had no muscle atrophy. These data indicate that further anatomic investigation into the relation between flank incision and abdominal wall innervation may contribute to prevention of muscle atrophy after flank incision.

Spontaneous rupture of the iliac vein: report of a case

We reprot a rare case of a spontaneous rupture of the iliac vein which was then surgically treated with good results. A 66-year-old woman was admitted complaining of leg swelling and lower abdominal pain. On the 3rd day after admission, an operation was performed because of a gradually increasing hematoma in the retroperitoneal space. Laparotomy revealed a 17 mm longitudinal tear on the anterior surface of the left external iliac vein with a thrombus inside the lumen. Most of the previously reported 14 cases of this nature have required emergency operations.

Extended surgery with en bloc resection of the right common iliac vessels for lymph node metastasis of mucinous colon carcinoma: report of a case.

Abstract We report herein the case of a 63-year-old woman who underwent surgery for recurrent mucinous carcinoma of the cecum. Recurrent metastatic lymph nodes had invaded the right common iliac vessels and right ureter, but she had no distant metastases and no peritoneal dissemination. Extended surgery with en bloc resection of the right iliac vessels and right ureter, and femorofemoral bypass were performed. Postoperatively, several complications developed which were successfully treated by further operations. By 1 year after surgery, she had no recurrent tumors on radio-logical examination, suggesting that our aggressive surgery with resection of the invaded regional vessels had effectively removed the recurrent tumors. This procedure may therefore significantly prolong the survival time and improve the quality of life of such patients.

Changing predictors of postoperative mortality in acute type A aortic dissection. Is only coronary artery compromise significant

OBJECTIVES Rapid emergency transport and early diagnosis and surgical treatment for acute type A aortic dissection have improved postoperative survival, which has, however, plateaued at about 80%. End-organ malperfusion is regarded as a strong predictor of postoperative mortality, replacing factors such as cardiac tamponade complications, aortic rupture, and left ventricular dysfunction due to aortic insufficiency. It is thus important to reevaluate risk factors for surgical death to assess current therapeutic strategies. METHODS We statistically analyzed potential risk factors for perioperative death in 88 patients undergoing surgical repair for type A aortic dissection between January 1990 and December 1999. RESULTS Univariate analysis showed that cardiopulmonary arrest (adjusted odds ratio: 13.78; p < 0.01) and malperfusion of more than 1 vital organ (adjusted odds ratio 4.97, p < 0.01), especially myocardial ischemia due to coronary artery dissection (adjusted odds ratio 3.21, p < 0.05), significantly increased the likelihood of operative death. Multivariate logistic regression analysis showed only cardiopulmonary arrest (p < 0.01) and concomitant coronary artery bypass grafting necessitated in cases complicated by evolving myocardial infarction (p < 0.05) to be independent predictors of postoperative mortality. CONCLUSION Preoperative complication from coronary dissection was the most important predictor of early postoperative mortality in this series. In such cases, rapid surgical intervention before myocardial infarction develops is vital to saving lives.

Stent graft treatment for thoracic and thoracoabdominal aortic disease using a unibody Z-stent that adapts to flexure.

Positioning a stent graft (SG) that adapts to the anatomical shape of the aorta is important to prevent complications after SG procedures to treat aortic disease. The Gianturco Z-stent has several benefits, but its rigid structure prevents adaptation to flexure. We improved this stent and studied its ability to adapt in the clinical environment. We positioned SGs and inspected their adaptability to flexure in an aortic arch model. We examined several gap lengths and strut directions, and determined the distance generated between the stent and the aortic wall. We found that adaptation was quite satisfactory with a gap of more than 10 mm or when the struts faced the major flexure or the side of the model aorta. Based on these findings and to facilitate placement, we manufactured the unibody Z-stent with 10-mm gaps. The unibody Z-stent was applied to treat thoracic and thoracoabdominal aortic disease in seven patients. The SG was positioned from the femoral or iliac artery in five patients and from an anastomosed graft to the ascending aorta after median sternotomy and bypass of the arch branches in two patients. A minor endoleak developed in one patient. None of the other six patients developed complications or died during the procedure, although one patient died in the hospital due to cerebral infarction. The unibody Z-stent was applied as a SG that adapts to flexure of the aorta and was easy to apply. The frequency of complications was apparently decreased after clinical application of the unibody Z-stent in SG treatment for thoracic and thoracoabdominal aortic disease.

Extra-Anatomical Bypass Grafting for Coarctation of the Aorta associated With Annuloaortic Ectasia Long-Term Outcome

Two patients each with a rare combination of aortic coarctation and annuloaortic ectasia underwent successful single-stage repair in which the aortic root was reconstructed with a valved conduit, and an extra-anatomical bypass was made by grafting from the ascending to the abdominal aorta. Although the long-term outcome of such a long extra-anatomical bypass graft has not yet been established, the use of the graft for reducing the risk to coarctation-related complications during the early and late postoperative periods appears promising.

Use of prothrombin fragment 1+2 for evaluating anticoagulant therapy after mechanical heart valve replacement

Prothrombin fragment 1+2 (F1+2) is a coagulation factor newly used as a molecular marker to monitor anticoagulant therapy in patients undergoing heart valve replacement. We evaluated the usefulness of F1+2 against that of prothrombin time (PT) reported as the internationalized normalized ratio (INR) in 93 patients undergoing mechanical heart valve implantation between August 1999 and July 2000. The study group consisted of 38 men and 55 women, with an average age of 61.1±11.2 years. The surgeries were 34 aortic replacements, 9 double valve replacements, and 50 mitral valve replacements. Warfarin doses were controlled based on PT-INR values at a target range of 1.5–2.5 F1+2 levels in the 0.4–1.2 nmol/l level were considered normal. No thromboembolism or bleeding complication occurred in any patient during the mean follow-up period of 12 months. The overall correction coefficient between F1+2 and PT-INR was 0.165 (P<0.001). A few specimens showed abnormally high levels of F1+2, even when PT-INR values were within the optimal range. The plasma levels of F1+2 that fell within normal range came from specimens with PT-INR values <1.50. The plasma levels of F1+2 that corresponded to PT-INR values of 1.50–2.50 fell just within the normal range, and the F1+2 levels corresponding to PT-INR values >2.50 were less than half of the lower limit of normal. Our analysis involving F1+2 confirmed PT-INR in the 1.5–2.5 range following mechanical heart valve implantation to be optimal. We found that using F1+2 to monitor individual response to anticoagulation therapy is useful when PT-INR values are difficult to obtain.