P177 Left atrial strain in patients with cardiac amyloidosis. Relationship to left atrial amyloid deposition focusing on prognosis

Background

 In cardiac amyloidosis (CA), the left atrium (LA) is frequently infiltrated by the amyloid fibrils. It is currently known that LA strain is a marker of LA function and prognosis in many cardiac diseases, however its significance in CA remains unknown. 

Purpose

 Our aim was to investigate correlation between LA strain measured by Cardiovascular Magnetic Resonance (CMR) and amyloid deposit in LA, and also evaluate the LA strain on the prognostic significance. 

Methods and results

 Of 74 consecutive patients with biopsy-proven CA, we analyzed 42 patients (age 72 ± 10 years; 76 % males) with contrast-enhanced CMR, and examined LA late gadolinium enhancement (LGE) and CMR derived LA strain using feature tracking method. Of the 42 patients, 29 patients (69 %) was transthyretin cardiac amyloidosis (ATTR-CA) in the majority. We divided these 42 patients into two groups according to the CMR measured peak atrial longitudinal strain (PALS) (> = or < median); high-strain (> = 6.67 %, n = 21) and low-strain (＜ 6.67 %, n = 21) and compared the patient’s characteristics, blood test data, echocardiography and CMR parameters. There were no significant differences between two groups in these parameters but in the extent of LA-LGE (54 % vs 80 %, p = 0.008). The PALS correlated with the extent of LA-LGE (ρ= 0.50, p = 0.001). In multivariate analysis including LVEF, E/e’ and BNP, LA-LGE was an independent determinant of PALS. During three-year follow up, the LA strain significantly related to heart failure hospitalization in the ATTR-CA patients (p = 0.036)(Figure). 

Conclusions

 In CA patients, CMR measured LA longitudinal strain correlates with the LA-LGE. It also provides useful information for poor prognosis of patients with ATTR-CA.

Abstract P177 Figure. Heart failure hospitalization in ATTR-CA

P642What is the most important residual risk after achievement of appropriate low-density lipoprotein cholesterol lowering therapy in secondary prevention of Japanese patients?

Background

In secondary prevention of coronary artery disease, target value of low-density lipoprotein cholesterol (LDL-C) <100mg/dL with using statins is recommended as standard therapy in Japanese guideline. However, impact of residual risks after achievement of standard LDL-C lowering therapy was not fully examined. Furthermore, there is little information whether more strict management of LDL-C lowering is effective to prevent long-term cardiovascular events than standard management.

Purpose

The purpose of this study was to evaluate the relationship between residual risks after achievement of standard LDL-C lowering therapy and long-term coronary events in secondary prevention of Japanese patients.

Methods

From January 2007 to August 2018, 333 patients with previous percutaneous coronary intervention underwent late coronary angiography to examine recurrence of cardiac ischemia beyond the early phase of restenosis. We defined appropriate LDL-C lowering therapy as achieved LDL-C <100mg/dL with using statins. Patients whose achieved LDL-C was <100mg/dL with using statins were classified as Appropriate-group (n=139), and patients who were not using statins or whose achieved LDL-C was ≥100mg/dL were classified as Inappropriate-group (n=194). Endpoints of the study were recurrence of cardiac ischemia as acute coronary syndrome (recurrence-ACS) and any late coronary revascularization.

Results

During average 7.1 years follow-up, 195 patients (59%) underwent any late coronary revascularization. In 91 of those patients, clinical presentation of recurrence-ACS was observed. Kaplan-Meier curve analysis revealed that the incidence of recurrence-ACS and any late coronary revascularization were significantly lower in Appropriate-group than in Inappropriate-group (p=0.017 and p<0.001, respectively). In Appropriate-group, recurrence-ACS was significantly lower in patients with achieved LDL-C <70mg/dL than in those with LDL-C 70 to <100mg/dL (p=0.042), however, any late revascularization was not different between the two groups. On the other hand, in Inappropriate-group, recurrence-ACS was significantly lower in patients with using statins than in those without using statins (p=0.038), and any late revascularization was less frequent in patients with achieved LDL-C <100mg/dL than in those with LDL-C ≥100mg/dL (p=0.035). Moreover, multivariate analysis identified that only LDL-C was an independent predictor of recurrence-ACS in Appropriate-group (HR: 1.047, p=0.006), in contrast, LDL-C (HR: 1.008, p=0.020), using statins (HR: 0.555, p=0.034) and triglyceride (HR: 1.003, p=0.038) were independent predictors of recurrence-ACS in Inappropriate-group.

Conclusions

LDL-C was the most important residual risk of recurrence-ACS even after recommended standard therapy has been achieved. More strict management of LDL-C targeting to <70mg/dL should be considered in secondary prevention of Japanese patients.

5195Growth differentiation factor-15 and mortality in suspected or known coronary heart disease patients with diabetes: a subanalysis of the ANOX study

Background

Diabetes is a risk factor for coronary heart disease (CHD), but further risk stratification in patients with diabetes is necessary to improve the prediction and prevention of cardiovascular events and deaths. Growth differentiation factor-15 (GDF-15) is a stress-responsive cytokine, which plays an important role in the regulation of the inflammatory response, growth and cell differentiation. Elevated GDF-15 was found in various diseases including diabetes and stable CHD, and was reported to predict mortality and cardiovascular events in general or established CHD population. However, the prognostic value of GDF-15 in suspected or known CHD patients with diabetes is unknown.

Methods

Serum GDF-15 levels were measured in 1,087 suspected or known CHD patients with diabetes undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict cardiovascular events (ANOX) study, and followed up for 3 years. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 147 patients died from any cause, 47 died from cardiovascular disease, and 94 developed MACE. After adjustment for established risk factors, GDF-15 levels were significantly associated with all-cause death (hazard ratio [HR] for 1-SD increase, 1.66; 95% confidence interval [CI], 1.48–1.86), cardiovascular death (HR, 1.63; 95% CI, 1.34–1.99), and MACE (HR, 1.41; 95% CI, 1.20–1.65). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of GDF-15 levels further improved the prediction of all-cause death (continuous net reclassification improvement [NRI], 0.344; 95% CI, 0.172–0.517; P<0.001; integrated discrimination improvement [IDI], 0.049; 95% CI, 0.026–0.072; P<0.001), but not that of cardiovascular death (NRI, −0.013; 95% CI, −0.300–0.274; P=0.931; IDI, 0.023; 95% CI, 0.003–0.043; P=0.026) or MACE (NRI, 0.059; 95% CI, −0.151–0.268; P=0.583; IDI, 0.005; 95% CI, −0.004–0.015; P=0.244).

Conclusions

In suspected or known CHD patients with diabetes undergoing elective coronary angiography, elevated GDF-15 levels may predict all-cause mortality independent of established risk factors and cardiovascular biomarkers.

Acknowledgement/Funding

The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization.

P5529Vascular endothelial growth factor-D and mortality in suspected or known coronary heart disease patients with diabetes: a subanalysis of the ANOX study

Background

Diabetes is a risk factor for coronary heart disease (CHD), but further risk stratification in patients with diabetes is necessary to improve the prediction and prevention of cardiovascular events and deaths. Vascular endothelial growth factor-D (VEGF-D) is a secreted glycoprotein that can act as lymphangiogenic and angiogenic growth factors through binding to its specific receptors, VEGFR-3 (Flt-4) and VEGFR-2 (KDR/Flk-1). VEGF-D signaling via VEGFR-3 plays an important role in lipoprotein metabolisms which may contribute to CHD. VEGF-D signaling has been used as a therapeutic target of human diseases such as lymphangioleiomyomatosis and refractory angina. Furthermore, in clinical settings, the VEGF-D level is already established as a diagnostic biomarker for lymphangioleiomyomatosis. However, the prognostic value of VEGF-D in suspected or known CHD patients with diabetes is unknown.

Methods

Serum VEGF-D levels were measured in 1,087 suspected or known CHD patients with diabetes undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict cardiovascular events (ANOX) study, and followed up for 3 years. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 147 patients died from any cause, 47 died from cardiovascular disease, and 94 developed MACE. After adjustment for established risk factors, VEGF-D levels were significantly associated with all-cause death (hazard ratio [HR] for 1-SD increase, 1.34; 95% confidence interval [CI], 1.21–1.47), cardiovascular death (HR, 1.40; 95% CI, 1.18–1.62), and MACE (HR, 1.22; 95% CI, 1.07–1.40). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-D levels further improved the prediction of all-cause death (continuous net reclassification improvement [NRI], 0.258; 95% CI, 0.088–0.429; P=0.003; integrated discrimination improvement [IDI], 0.013; 95% CI, 0.002–0.024; P=0.022), but not that of cardiovascular death (NRI, 0.046; 95% CI, −0.245–0.336; P=0.759; IDI, 0.013; 95% CI, −0.005–0.031; P=0.146) or MACE (NRI, 0.064; 95% CI, −0.146–0.274; P=0.552; IDI, 0.001; 95% CI, −0.002–0.004; P=0.557).

Conclusions

In suspected or known CHD patients with diabetes undergoing elective coronary angiography, elevated VEGF-D levels may predict all-cause mortality independent of established risk factors and cardiovascular biomarkers.

Acknowledgement/Funding

The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization

P5526Vascular endothelial growth factor-D and mortality in suspected or known coronary heart disease patients with chronic kidney disease: a subanalysis of the ANOX study

Background

Chronic kidney disease (CKD) is an independent risk factor for the development and progression of coronary heart disease (CHD). Vascular endothelial growth factor-D (VEGF-D) is a secreted glycoprotein that can act as lymphangiogenic and angiogenic growth factors through binding to its specific receptors, VEGFR-3 (Flt-4) and VEGFR-2 (KDR/Flk-1). VEGF-D signaling via VEGFR-3 plays an important role in lipoprotein metabolisms which may contribute to CHD. VEGF-D signaling has been used as a therapeutic target of human diseases such as lymphangioleiomyomatosis and refractory angina. Furthermore, in clinical settings, the VEGF-D level is already established as a diagnostic biomarker for lymphangioleiomyomatosis. However, the prognostic value of VEGF-D in suspected or known CHD patients with CKD is unknown.

Methods

Serum VEGF-D levels were measured in 999 suspected or known CHD patients with CKD undergoing elective coronary angiography, enrolled in the development of novel biomarkers related to angiogenesis or oxidative stress to predict cardiovascular events (ANOX) study, and followed up for 3 years. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

During the follow-up, 154 patients died from any cause, 61 died from cardiovascular disease, and 96 developed MACE. After adjustment for established risk factors, VEGF-D levels were significantly associated with all-cause death (hazard ratio [HR] for 1-SD increase, 1.41; 95% confidence interval [CI], 1.27–1.56), cardiovascular death (HR, 1.48; 95% CI, 1.28–1.71), and MACE (HR, 1.34; 95% CI, 1.18–1.53). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF-D levels further improved the prediction of all-cause death (continuous net reclassification improvement [NRI], 0.272; 95% CI, 0.100–0.445; P=0.002; integrated discrimination improvement [IDI], 0.015; 95% CI, 0.003–0.027; P=0.013), but not that of cardiovascular death (NRI, 0.230; 95% CI, −0.029 to 0.488; P=0.082; IDI, 0.012; 95% CI, −0.007 to 0.031; P=0.207) or MACE (NRI, 0.102; 95% CI, −0.106 to 0.310; P=0.337; IDI, 0.005; 95% CI, −0.005 to 0.015; P=0.337).

Conclusions

In suspected or known CHD patients with CKD undergoing elective coronary angiography, elevated VEGF-D levels may predict all-cause mortality independent of established risk factors and cardiovascular biomarkers.

Acknowledgement/Funding

The ANOX study is supported by a Grant-in-Aid for Clinical Research from the National Hospital Organization

P3765Low vascular endothelial growth factor-C was a predictor for cardiovascular events in patients with atrial fibrillation and suspected or known coronary artery disease: a subanalysis of the ANOX study

Background

Lymphatic system has been considered to play an important role in cardiovascular disease. We recently reported that vascular endothelial growth factor-C (VEGF-C), a central player in lymphangiogenesis, predicted all-cause mortality in patients with suspected or known coronary artery disease (CAD). However, relationship between VEGF-C and atrial fibrillation (AF) remains unclear.

Methods

The ANOX study is a multicenter, prospective cohort study of 2,418 patients with suspected CAD, to determine the predictive value of possible novel biomarkers related to angiogenesis or oxidative stress for major adverse cardiovascular events (MACE) among patients undergoing elective angiography. Blood samples were collected from the arterial catheter sheath at the beginning of coronary angiography. Serum levels of VEGF-C, as well as N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitivity troponin-I (cTnI), and high-sensitivity C-reactive protein (hsCRP), were measured. The outcome was a MACE defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke.

Results

Of a total of 2,418 patients, 261 patients had AF at baseline. AF group were older, and had more chronic kidney disease, history of heart failure, and history of stroke, but less diabetes, dyslipidemia, and CAD. The median level of NT-proBNP, cTnI, and hsCRP were higher in AF group [AF vs non-AF: NT-proBNP, 1048 pg/ml vs 162 pg/ml (p<0.0001); cTnI, 0.0003 ng/ml, vs 0.0 ng/ml (p<0.0001); hsCRP, 1.43 ug/ml vs 0.88 ug/ml (p=0.0005)], whereas median level of VEGF-C was lower in AF group [3107 pg/ml vs 3590 pg/ml (p<0.0001)]. AF was associated with lower VEGF-C and higher hsCRP after adjustment for potential confounders. During the 3-year follow-up, 29 (11.1%) patients in AF group and 136 (6.3%) patients in non-AF group developed MACE (p=0.007). Incidence of stroke was higher in AF group (17 (6.5%) vs 52 (2.4%); p<0.0009), despite that the incidence of cardiovascular death and myocardial infarction were similar between the groups. We divided the entire cohort into two groups based on the lowest quartile of VEGF-C or highest quartile of other biomarkers, lowest quartile of VEGF-C (log rank p=0.0004), as well as highest quartile of cTnI (log rank p=0.0009), were significantly associated with MACE in AF group. After adjustment for established risk factors and these biomarkers, both lowest quartile of VEGF-C (HR, 2.73; 95% CI, 1.27–6.06) and highest quartile of cTnI (HR, 2.54; 95% CI, 1.08–6.09) were significantly associated with MACE in AF group.

Conclusions

AF was associated with lower level of VEGF-C, and low VEGF-C as well as high cTnI might serve as an independent predictor of MACE in patients with AF and suspected or known CAD.

P1038Device implantation after catheter ablation of paroxysmal atrial fibrillation with coexisting sick sinus syndrome: Insights from the Kansai Plus Atrial Fibrillation (KPAF) study

Background

Sick sinus syndrome (SSS) and atrial fibrillation (AF) frequently coexist and interact to initiate and perpetuate each other. Several retrospective or small cohort studies have suggested that successful catheter ablation of AF may help to waive device implantations in patients with paroxysmal AF plus SSS, however, no prospective large studies are so far available on this scenario.

Purpose

We aimed to elucidate the device implantation-free survival after catheter ablation of paroxysmal AF with coexisting SSS in a prospective large-scale registry. We also determined the risk factors for device implantations after catheter ablation of paroxysmal AF.

Methods

The Kansai Plus Atrial Fibrillation (KPAF) study is a multi-center prospective registry that enrolled 5,019 consecutive patients that underwent an initial pulmonary vein isolation-based radiofrequency catheter ablation of AF. This study was comprised of 3,226 patients with paroxysmal AF registered in the KPAF study (age, 64.8±10.5 years old; female, n=999 [31.0%]; left atrial diameter [LAD], 37.5±8.0 mm; left ventricular ejection fraction [LVEF], 65.3±8.4%, CHADS2 score, 1.09±1.05). The atrial tachyarrhythmia-free and device-free survivals after catheter ablation were compared between patients with SSS (n=368; tachy-brady syndrome, 88%) and without SSS (control; n=2,858).

Results

The atrial tachyarrhythmia-free survival was almost identical between the two groups both after the first ablation session (Fig.1A) and after the last procedure with an average of 1.3±0.5 sessions. At baseline, the devices had already been implanted in 53 (14.4%) SSS and 36 (1.3%) control patients. In the remaining patients, devices were newly implanted in 54 (17.1%) SSS and 62 (2.2%) control patients during the follow-up of 3 years after the catheter ablation (Figure 1B). In the SSS group, devices were implanted predominantly within 6 months after the catheter ablation, and atrial tachyarrhythmia recurrence preceded the device implantation in 48 (89%) patients. Multivariate predictors of device implantations after the paroxysmal AF ablation included: SSS (hazard ratio [HR] 6.85, 95% confidence interval [CI] 4.61–10.19, p<0.001), an age>75 years old (HR 1.69, 95% CI 1.08–2.64, p=0.019), a female gender (HR 2.16, 95% CI 1.44–3.24, p<0.001), the LAD (mm) (HR 1.05, 95% CI 1.02–1.08, p=0.006), and the LVEF (%) (95% CI 0.96, 95% CI 0.94–0.98, p<0.001).

Figure 1

Conclusions

Device implantations could be waived in >80% of patients with SSS at 3 years of follow-up after the catheter ablation of paroxysmal AF in this real world all comer prospective registry. In addition to coexisting SSS, predictors of device implantations after paroxysmal AF ablation included: the elderly, a female gender, a large LA, and a reduced LVEF.

Acknowledgement/Funding

None

Functional analysis of a novel G87V TNFRSF1A mutation in patients with TNF receptor-associated periodic syndrome

Tumor necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS) is an autoinflammatory disease that is caused by heterozygous mutations in the TNFRSF1A gene. Although more than 150 TNFRSF1A mutations have been reported to be associated with TRAPS phenotypes only a few, such as p.Thr79Met (T79M) and cysteine mutations, have been functionally analyzed. We identified two TRAPS patients in one family harboring a novel p.Gly87Val (G87V) mutation in addition to a p.Thr90Ile (T90I) mutation in TNFRSF1A. In this study, we examined the functional features of this novel G87V mutation. In-vitro analyses using mutant TNF receptor 1 (TNF-R1)-over-expressing cells demonstrated that this mutation alters the expression and function of TNF-R1 similar to that with the previously identified pathogenic T79M mutation. Specifically, cell surface expression of the mutant TNF-R1 in transfected cells was inhibited with both G87V and T79M mutations, whereas the T90I mutation did not affect this. Moreover, peripheral blood mononuclear cells (PBMCs) from TRAPS patients harboring the G87V and T90I mutations showed increased mitochondrial reactive oxygen species (ROS). Furthermore, the effect of various Toll-like receptor (TLR) ligands on inflammatory responses was explored, revealing that PBMCs from TRAPS patients are hyper-responsive to TLR-2 and TLR-4 ligands and that interleukin (IL)-8 and granulocyte-macrophage colony-stimulating factor (GM-CSF) are likely to be involved in the pathogenesis of TRAPS. These findings suggest that the newly identified G87V mutation is one of the causative mutations of TRAPS. Our findings based on unique TRAPS-associated mutations provide novel insight for clearer understanding of inflammatory responses, which would be basic findings of developing a new therapeutic and prophylactic approach to TRAPS.

Peripheral administration of κ-opioid receptor antagonist stimulates gonadotropin-releasing hormone pulse generator activity in ovariectomized, estrogen-treated female goats

Pulsatile gonadotropin-releasing hormone (GnRH) secretion is indispensable for reproduction in mammals. Kisspeptin neurons in the hypothalamic arcuate nucleus (ARC), referred to as KNDy neurons because of the coexpression of neurokinin B and dynorphin A, are considered as components of the GnRH pulse generator that produces rhythmic GnRH secretion. The present study aimed to investigate if peripheral administration of PF-4455242, a κ-opioid receptor (KOR, a dynorphin A receptor) antagonist, facilitates pulsatile luteinizing hormone (LH) secretion and GnRH pulse generator activity in estrogen-treated ovariectomized Shiba goats to determine the possibility of using KOR antagonists to artificially control ovarian activities. PF-4455242 was intravenously infused for 4 h (1 or 10 μmol/kg body weight/4 h) or as a single subcutaneous injection (1 or 10 μmol/kg body weight). In a separate experiment, the same KOR antagonist (10 μmol/kg body weight/4 h) was intravenously infused during the recording of multiple unit activity (MUA) in the ARC that reflects the activity of the GnRH pulse generator to test the effects of KOR antagonist administration on GnRH pulse generator activity. Intravenous infusion and single subcutaneous injection of the KOR antagonist significantly increased the frequency of LH pulses compared with controls. Intravenous infusion of KOR antagonist also significantly increased the frequency of episodic bursts in the MUA. The present study demonstrates that peripherally administered KOR antagonist stimulates pulsatile LH secretion by acting on the GnRH pulse generator, and peripheral administration of PF-4455242 can be used to facilitate pulsatile LH secretion, which in turn facilitates ovarian activities in farm animals.

Quality control of hospital preparations: Establishment of a simple and rapid method for quantifying ulinastatin in vaginal suppositories

Ulinastatin vaginal suppositories, used to prevent threatened premature delivery, are frequently used in hospitals. However, there is no established method for quantifying ulinastatin contained in suppositories. Therefore, we investigated a simple and efficient method for quantifying ulinastatin contained in suppositories. Our analytical method involved removal of the base; optimising the enzyme inhibition reaction time and enzyme reaction time; and measuring the absorbance. The modified method was reproducible, operation time was significantly shortened, and cost was reduced to approximately 1/17 of that of the previously reported method. This simple and rapid quantitative method could contribute to the improvement of quality control of ulinastatin vaginal suppositories as an extemporaneous hospital preparation.

Probiotic Lactobacillus gasseri SBT2055 improves insulin secretion in a diabetic rat model

The probiotic Lactobacillus gasseri SBT2055 (LG2055) has a protective effect against metabolic syndrome in rats and humans. Metabolic syndrome increases the risk of type 2 diabetes mellitus. In this study, Goto-Kakizaki rats were used as a diabetic model and fed diets containing LG2055-fermented or nonfermented skim milk for 4 wk. Indices of diabetes such as blood glucose levels, serum glucagon levels, plasma levels of insulin, C-peptide, and glucagon-like peptide-1, tissue glycogen contents, and pancreatic mRNA levels were measured. The plasma C-peptide levels and pancreatic mRNA levels of insulin genes (Ins1 and Ins2) and Pdx1 (a transcriptional factor of insulin genes) were increased in LG2055 diet-fed rats. The increase in insulin secretion corresponded to an improvement in serum and pancreatic inflammatory status, associated with decreases in serum levels of serum amyloid P and pancreatic levels of granulocyte colony-stimulating factor. Insulin resistance in Goto-Kakizaki rats was ameliorated by increased glycogen storage in the liver and quadriceps femoris muscles and decreased serum free fatty acid levels. This improvement may be related to the increased cecal production of short-chain fatty acids. In conclusion, dietary LG2055 improved insulin secretion in diabetic rats by improving the inflammatory status in the pancreas and serum.

Comparison of osseous healing after sagittal split ramus osteotomy and intraoral vertical ramus osteotomy

The sagittal split ramus osteotomy (SSRO) is generally associated with greater postoperative stability than the intraoral vertical ramus osteotomy (IVRO); however, it entails a risk of inferior alveolar nerve damage. In contrast, IVRO has the disadvantages of slow postoperative osseous healing and projection of the antegonial notch, but inferior alveolar nerve damage is believed to be less likely. The purposes of this study were to compare the osseous healing processes associated with SSRO and IVRO and to investigate changes in mandibular width after IVRO in 29 patients undergoing mandibular setback. On computed tomography images, osseous healing was similar in patients undergoing SSRO and IVRO at 1year after surgery. Projection of the antegonial notch occurred after IVRO, but returned to the preoperative state within 1year. The results of the study indicate that IVRO is equivalent to SSRO with regard to both bone healing and morphological recovery of the mandible.