Tissue responses to everolimus-eluting stents implanted in severely calcified lesions following atherectomy

Histopathological examination has revealed that stents on severely calcified plaques were associated with delayed vascular healing. Although atherectomy devices can increase the number of malapposed struts, tissue responses to implanted drug eluting stents in atherectomy patients remain largely unknown. This retrospective observational study included 30 patients who underwent atherectomy and everolimus-eluting stent (EES) deployment for severely calcified coronary lesions (biodegradable polymer EES (BP-EES), n = 15; durable polymer EES (DP-EES), n  = 15). Optical coherence tomography was carried out at baseline and follow-up, and struts with acute stent malapposition (ASM) were categorized as struts on modified calcium (mod-Ca), non-modified calcium (non-mod-Ca), or non-calcium (non-Ca). Adequate vascular healing, defined as ASM resolution with neointimal coverage, was compared between the BP-EES and DP-EES groups. Multivariate linear regression analysis using a generalized estimated equation revealed that BP-EES use was associated with significantly better adequate vascular healing compared with DP-EES (odds ratio [OR]: 3.691, 95% confidence interval [CI] 1.175-11.592, P = 0.025). adequate vascular healing was associated with the underlying plaque morphology (mod-Ca vs non-mod-Ca: OR 2.833, 95% CI 1.491-5.384, P = 0.001; non-Ca vs non-mod-Ca: OR 1.248, 95% CI 0.440-3.543, P = 0.677). This study demonstrates that drug-eluting stent selection and calcium modification are possible factors affecting vascular healing of malapposed struts in severely calcified lesions.

Impact of cystatin C-derived glomerular filtration rate in patients undergoing transcatheter aortic valve implantation

Background

Chronic kidney disease (CKD) impacts prognosis in patients undergoing transcatheter aortic valve implantation (TAVI). While estimated glomerular filtration rate (eGFR) calculated from serum creatinine [eGFR (creatinine)] is affected by body muscle mass which reflects frailty, eGFR calculated from serum cystatin C [eGFR (cystatin C)] is independent of body composition, resulting in better renal function assessment.

Methods

This study included 390 consecutive patients with symptomatic severe aortic stenosis (AS) who underwent TAVI, and measured cystatin C-based eGFR at discharge. Patients were divided into two groups, with or without CKD estimated with eGFR (cystatin C). The primary endpoint of this study was the 3-year all-cause mortality after TAVI.

Results

The median patient age was 84 years, and 32.8% patients were men. Multivariate Cox regression analysis indicated that eGFR (cystatin C), diabetes mellitus, and liver disease were independently associated with 3-year all-cause mortality. In the receiver-operating characteristic (ROC) curve, the predictive value of eGFR (cystatin C) was significantly higher than that of eGFR (creatinine). Furthermore, Kaplan-Meier estimates revealed that 3-year all-cause mortality was higher in the CKD (cystatin C) group than that in the non-CKD (cystatin C) group with log-rank p = 0.009. In contrast, there was no significant difference between the CKD (creatinine) and non-CKD (creatinine) groups with log-rank p = 0.94.

Conclusions

eGFR (cystatin C) was associated with 3-year all-cause mortality in patients who underwent TAVI, and it was superior to eGFR (creatinine) as a prognostic biomarker.

Left atrial volume index predicts future improvement of B-type natriuretic peptide levels after transcatheter aortic valve replacement

In patients with symptomatic severe aortic stenosis (AS), those who experienced readmission due to heart failure after transcatheter aortic valve replacement (TAVR) showed poor prognosis. Furthermore, poor B-type natriuretic peptide (BNP) improvement is associated with increased morbidity and mortality. However, little is known about the clinical parameters related to the change in BNP levels after TAVR procedure. This study population consisted of 127 consecutive patients of symptomatic severe AS with preserved ejection fraction (EF) who underwent transfemoral TAVR (TF-TAVR). Comprehensive transthoracic echocardiography was performed prior to the day of TF-TAVR. BNP was measured serially before and 1 year after TF-TAVR. The median BNP level was significantly decreased from 252.5 pg/ml to 146.8 pg/ml in all 127 patients 1 year after TF-TAVR (P < 0.01). However, the patients could be divided into 2 groups according to decrease (72%) or increase (28%) in plasma BNP level. Multivariate logistic regression analysis revealed that Aortic valve (AV) peak velocity, pre-procedural BNP, and larger left atrial volume index (LAVI) were found to be an independent predictor of increased BNP level 1 year after TAVR (OR 0.55, 95% CI 0.38-0.77; P < 0.01). LAVI were negatively correlated with the change in BNP level before and 1 year after TAVR (r = 0.47, P < 0.01). The ROC analysis demonstrated that 52.9 ml/m2 was the optimal cut-off value of LAVI for decreasing BNP 1 year after TAVR (area under the curve 0.69) with 64% sensitivity and 70% specificity. In addition to AV peak velocity and pre-procedural BNP, LAVI independently predicts future improvement of BNP levels 1 year after TAVR. Our findings indicate an additive predictive value of assessment of LAVI before TAVR procedure for risk stratification.

Early recurrence of hyperthyroidism in patients with Graves' disease treated by subtotal thyroidectomy

Prerequisites for surgical treatment of Graves' disease are that it can be done safely and that it is associated with a low incidence of recurrent hyperthyroidism. Early recurrence is especially undesirable. We studied 728 patients with Graves' disease treated by subtotal thyroidectomy using multivariate analysis in order to determine the factors related to early recurrence. The following factors were analyzed: age, sex, duration of medical treatment, weight of resected thyroid tissue, thyroid remnant size, preoperative level of thyroid-stimulating hormone (TSH) binding inhibitory immunoglobulin (TBII), and antimicrosomal hemagglutination antibody (MCHA). "Early recurrence" was defined as TSH suppression observed within the first year after surgery and continuing for at least 6 months. A total of 106 patients (14.6%) had early recurrence. Statistical analyses were performed by the chi-square test for univariate analysis and a logistic model for multivariate analysis. Significant factors were thyroid remnant size, MCHA, and TBII. These results indicated that TBII and MCHA are related to early recurrence of hyperthyroidism, and smaller remnant size is recommended for patients with a high MCHA titer or a high TBII level (or both) in order to avoid early recurrence.

Metastases to the regional lymph nodes, lymph node recurrence, and distant metastases in nonadvanced papillary thyroid carcinoma

To investigate the biological characteristics of papillary thyroid carcinoma from the perspectives of lymph node metastasis, lymph node recurrence, and distant metastasis, 746 patients with nonadvanced papillary thyroid carcinoma were retrospectively studied. There were 76 men and 670 women with a mean age of 42.7 years. The rate of lymph node metastasis was significantly higher in young patients (aged less than 30 years). Lymph node recurrence was observed in 80 patients and distant metastasis in 13, being seen with significant frequency in the young and elderly (aged over 50 years) patients and in the men. The frequency of distant metastasis was significantly greater in the elderly patients and in those with lymph node recurrence. These findings indicate that the role of regional lymph nodes and the clinical meaning of lymph node recurrence differ between young and elderly patients.

[Regional lymph node recurrence in patients with papillary thyroid carcinoma who did not undergo neck dissection]

It is important and difficult problem to manage patients with thyroid nodules which are indeterminate as papillary thyroid carcinoma (PTC) before surgery and identified as PTC after surgery. This paper highlighted whether immediate reoperation for such patients should be undergone or not. The prognosis of 196 patients with PTC who underwent lobectomy or subtotal thyroidectomy without neck dissection were studied (non-dissection group). The controls consisted of 783 patients with non-advanced PTC who underwent radical surgery during the same period (dissection group). There was no death due to PTC in both groups. Distant metastasis was observed 1.5% in non-dissection group and 2.2% in the dissection group. Local recurrence was observed 9.7% in the non-dissection group and 11.2% in the dissection group. The results suggested that immediate reoperation for the patient's who did not undergo neck dissection, is not necessary. It is thought that all of lymph node metastasis detected only by histology does not always behave in same.

Surgical treatment of locally advanced thyroid cancer

Eighty-four patients with locally advanced thyroid cancer treated during the period from 1965 to 1989 were studied in order to evaluate the appropriateness of radical surgery. There were 57 patients who underwent palliative surgery (palliative group) and 27 patients who underwent radical surgery (radical group). Forty-six of the patients in the palliative group and all 27 in the radical group were aged 40 years or more. The survival rates as analyzed by the Kaplan-Meier method revealed no significant difference between patients aged 40 or more in the palliative group and those in the radical group. The control of local disease, however, was much more difficult in the palliative group. From the view of survival rates, the superiority of radical surgery could not be demonstrated, but radical surgery did control local neck disease better. In the palliative group, the survival rate of patients aged under 40 was significantly better than that of patients aged 40 or more. It may thus be better to avoid radical surgery in patients under 40 if it would result in a severe deterioration in their quality of life.

[Hyalinizing trabecular adenoma of the thyroid]

We experienced a very rare case of hyalinizing trabecular adenoma of the thyroid. The histopathological features of this case included the following. 1) In puncture-aspiration cytodiagnosis, tumor cells aggregated around pink-stained hyaline acellular areas in an ellipsoidal or spindly configuration, with a part of the cytoplasm appearing as filamentous with unclear borders. In addition, a large number of intranuclear "holes" and nuclear grooves were evident. 2) In biopsy, tumor cells appeared in ellipsoidal or spindly configuration, with cytoplasm that easily stained with thyroglobulin but did not stain with calcitonin. The nuclei were irregular in size and some of the nuclei appeared strongly atypical, occasionally seen with cytoplastic inclusion body in the nucleus. These cells showed funicular structures in a radical arrangement with a hyaline material at the center. The hyaline material was stained positively with PAS or Laminin, but not with Cong red.

[Prognostic factors of papillary carcinomas of the thyroid gland--retrospective multivariate analysis of 227 patients with median follow-up 130 months]

I carried out the retrospective analysis of the prognostic factors of papillary carcinoma of the thyroid gland by using Cox's proportional hazard model using SAS program, and obtained the following conclusions. Two hundred and twenty seven patients who received surgical treatment under the diagnosis of carcinoma of the thyroid in the 1st Department Surgery of Yokohama City University during 24 years from 1964 to 1987 were subjected to this study. As prognostic factors, sex, age at the diagnosis, size of the tumor, presence of lymph node metastasis, number of the metastatic lymph nodes, presence of the local infiltration, presence of the distant metastasis and thyroidectomy were investigated. From these results, age at the diagnosis (chi 2 = 18.93, p < 0.0001, beta = 0.06, risk ratio = 0.203), presence of the local infiltration (chi 2 = 14.55, p < 0.0001, beta = 0.75, risk ratio = 0.175) and sex (chi 2 = 7.63, p < 0.01, beta = -0.91, risk ratio = 0.175) were considered statistically significant. Patients over 50 years of age at the diagnosis and presence of the local infiltration had high risk of death from papillary carcinoma of the thyroid gland. Particularly, age at the diagnosis was the most important prognostic factor. Therefore, it was considered that therapeutic approach taking age into consideration is important for the treatment of papillary carcinoma of the thyroid.

Does total thyroidectomy induce metabolic bone disturbance?

Bone mineral content of 38 thyroidectomized patients with well differentiated thyroid carcinoma were determined. Seventeen patients were totally thyroidectomized and 21 patients were non-totally thyroidectomized (lobectomy). Thirty-eight healthy males and females were served as age-matched controls. Trabecular bone mineral content of lumbar vertebra was evaluated by quantitative CT method. Bone metabolic parameters in serum were measured. No significant differences were observed in the mean bone mineral content and BMC-index of totally thyroidectomized patients compared with non-totally thyroidectomized patients and control. Serum calcitonin level was not reduced in totally thyroidectomized. It is concluded that after total thyroidectomy, bone metabolic disturbance was not significant, and that when calcitonin remained at its basal level, it had no effects on bone metabolism.

[Does L-thyroxine administration in a dose to suppress TSH secretion induce metabolic bone disturbance in patients with thyroid carcinoma?]

We investigated whether L-thyroxine for TSH suppression may induce metabolic bone disturbance, especially in trabecular bone. Subjects were 75 premenopausal women (mean age: 37.7) who underwent surgery at Ito Hospital or Yokohama City University Hospital from 1972 to 1988 for differentiated thyroid carcinoma. All of them received L-thyroxine for the purpose of TSH suppression. According to the duration of the drug therapy after surgery, they were divided into 3 groups: Group I patients were treated for more than 10 years after surgery (17 cases), Group II from 5 to 10 years (28 cases), and Group III less than 5 years (30 cases). The control group was consisted of 15 premenopausal women (mean age: 37.0). There was no significant difference in age among these 4 groups. Quantitative CT was used for evaluation of trabecular bone mineral content. Mean bone mineral contents determined in Group I, Group III, Group II and control group patients were 204.7, 213.1, 207.6, 222.6 mg/cm3, respectively. There was no significant difference among them. It is concluded that L-thyroxine can be administered safely without metabolic disturbance in trabecular bone.

[The excisional range of tracheal infiltration of the thyroid cancer]

We studied histopathologically the infiltrative modes in 17 cases with tracheal infiltration of the thyroid cancer, and studied its excisional range. 1) Macroscopically, morphologies in the regions of the trachea were divided into 3 types. Types I and II were noted in 4 cases for each and Type III was noted in 9 cases. 2) When the infiltrative modes in the trachea were divided into localized and infiltrative types, localized type was noted in all cases of type I, and infiltrative type was noted in all cases of Type II. The both types were noted in 2 cases and 7 cases of Type III, respectively. 3) Infiltrative region of the tracheal mucous membrane in all cases of Types I and III was localized in the range of the infiltrative region of the extratracheal mucous membrane. The infiltrative region of the tracheal mucous membrane was wider in 2 cases of Type II comparing with that of the extratracheal mucous membrane. It is considered that radical treatment of types I and III can be obtained by the excisional range of the infiltration of the extratracheal mucous membrane. Operative diagnosis is necessary because wider range infiltration of the cancer is observed in the tracheal mucous membrane of Type II.

[Meaning in measurement of bone mineral content as preoperative evaluation of aged patients]

Recently, mean span of life has been prolonged, and extensive operations are performed on aged patients. However, there are cases which have a difference between their chronological and actual ages. Bone mineral content (BMC) decreases with age and the decrease in BMC might suggest deterioration of immunological competence as observed in osteoporosis. Whether BMC can be an index for evaluation of geriatric patients' actual age from the aspect of immunological competence was investigated. Subjects were 54 cases aged more than 60. Twenty-one healthy young males and females were enrolled as the control group. Quantitative CT is used for assessment of BMC. The value obtained by dividing BMC by the standard BMC of the same age and sex, was defined as BMC index. BMC indices of normal BMC group were more than 0.8 and those of decreased BMC group were less than 0.8. Some immunological markers were investigated. Lymphocyte subset OKT3+ was reduced and juvenile lymphocytes expressed by OKT6+ and OKT3+-(OKT4+ + OKT8+) increased (corrected). Increased in juvenile lymphocyte and decrease in lymphocyte blast transformation and competence of generating interleukin 2 were observed in decreased BMC group. BMC is useful as preoperative evaluation for geriatric operative cases and patients of BMC index below 0.8 need to be paid attention to postoperative infection.

Prediction of distant metastasis in follicular adenocarcinoma of the thyroid

Follicular adenocarcinoma of the thyroid sometimes displays distant metastasis in spite of its low histological grade of malignancy. We have studied whether distant metastasis can be detected by the presence of blood vessel invasion. We have also examined the problem from the viewpoint of cell-to-cell conjugation. This study examined 160 cases of follicular adenocarcinoma of the thyroid. Histological specimens were made by sectioning tumors at their largest diameter. Blood vessel endothelia were specifically stained immunohistochemically with factor VIII-related antigen and Ulex europeaus agglutinin I (UEA-1). Then, the presence of blood vessel invasion was examined in detail. Furthermore, the conjugation of lectin-derived wheat germ agglutinin (WGA) to tumor cells was examined. Conjugation of tumor cells was also examined using sialic acid as a marker. Blood vessel invasion was recognized in 95 (59.4%) of 160 cases. Distant metastases were identified in 25 cases (15.6%) in which blood vessel invasion was also found. Relative to the group without distant metastases, the group with distant metastases showed not only a significantly higher sialic acid content but also higher levels of WGA-binding protein in the tissues. The risk of distant metastasis in patients with follicular adenocarcinoma of the thyroid appears to be related both to the extent and to the frequency of blood vessel invasion. Furthermore, assessment of the conjugation of cells appears to have predictive value for occurrence of distant metastases.

[Bone metabolism in thyroidectomized patients--evaluation of bone mineral content by quantitative CT]

The bone mineral content in the patients who had undergone operation for thyroid carcinoma was measured by quantitative CT. Thirty-eight cases were enrolled as the subjects. All cases were papillary adenocarcinoma of the thyroid. The totally thyroidectomized group consisted of 3 males and 14 females, and the non-totally thyroidectomized group (post-lobectomy) 3 males and 18 females. Thirty-eight healthy males and females were assigned to the control group. For evaluation of bone mineral content, quantitative CT was used and bone mineral content in the patient's lumbar vertebrae was measured. Concurrently, bone metabolic parameter in serum was determined. No significant difference was observed in the mean bone mineral content among the above three groups. To make correction by sex and age, BMC-index was defined as the value that the bone mineral content in each case was divided by the standard mean by the same age and sex. No significant difference was observed in BMC-index among the above three groups. No significant correlation was observed in serum calcitonin level with the bone mineral content and BMC-index. It suggests that no influence is exerted on bone metabolism if serum calcitonin is maintained in the physiological level.