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ABSTRACT: We report a case of a large intra-aortic thrombosis in an 83-year-old woman concurrent with metastatic mediastinal leiomyosarcoma. Imaging studies incidentally detected a mediastinal malignant tumour metastasising to bilateral adrenals and an extensive intra-aortic mass that was suspected to be intra-aortic thrombosis. One month later massive embolism developed in the lower limb and her condition deteriorated rapidly resulting in death. Autopsy revealed diffused proliferation of highly pleomorphic atypical cells accompanied by necrosis in the mediastinum tumours and bilateral adrenal glands. Leiomyosarcoma metastasising to bilateral adrenals was confirmed by the results of immunostaining. The intra-aortic mass suggested that the fragmented thrombus might be the cause of a sudden lower-limb embolism. Microscopic examination showed that the mass lesion in the aortic arch was composed of a blood clot containing neutrophils. We report this case because leiomyosarcoma arising from the mediastinum and, especially, associated with an extraordinarily large intra-aortic thrombosis is very rare.
Case Reports 01/2013; 2013.
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ABSTRACT: Recent studies have reported the clinical usefulness of positive airway pressure ventilation therapy with various kinds of pressure support compared with simple continuous positive airway pressure (CPAP) for heart failure patients. However, the mechanism of the favorable effect of CPAP with pressure support can not be explained simply from the mechanical aspect and remains to be elucidated.
In 18 stable chronic heart failure patients, we performed stepwise CPAP (4, 8, 12 cm H(2)O) while the cardiac output and intracardiac pressures were continuously monitored, and we compared the effects of 4 cm H(2)O CPAP with those of 4 cm H(2)O CPAP plus 5 cm H(2)O pressure support. Stepwise CPAP decreased cardiac index significantly in patients with pulmonary arterial wedge pressure (PAWP) <12 mm Hg (n = 10), but not in those with PAWP ≥12 mm Hg (n = 8). Ventilation with CPAP plus pressure support increased cardiac index slightly but significantly from 2.2 ± 0.7 to 2.3 ± 0.7 L min(-1) m(-2) (P = .001) compared with CPAP alone, regardless of basal filling condition or cardiac index.
Our results suggest that CPAP plus pressure support is more effective than simple CPAP in heart failure patients and that the enhancement might be induced by neural changes and not simply by alteration of the preload level.
Journal of cardiac failure 12/2012; 18(12):912-8. · 3.25 Impact Factor
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ABSTRACT: In detecting coronary artery disease (CAD), fusion images obtained by combining myocardial perfusion imaging (MPI) and computed tomography coronary angiography (CTCA) have shown a higher accuracy and clinical usefulness than these modalities used separately or a simple comparison of individual images. However, the clinical use of fusion images has been restricted by the necessity of obtaining images with an integral type device or with devices made by the same manufacturer. Thus, we evaluated the detection of hemodynamically significant CAD by fusion images created with a newly developed general-purpose application that can be used with any type of device.
In 49 patients, MPI during exercise and at rest and CTCA were obtained separately and combined into fusion images using the new application. As the reference standard, a comparative interpretation of MPI and the conventional coronary arteriography (CAG) was adopted. Hemodynamically significant CAD were diagnosed when MPI showed a reversible perfusion defect in a region with greater than 50% luminal stenosis on CAG. The capability of fusion images to detect CAD was compared with that of CTCA images alone. Fusion images showed a higher ability to detect CAD (sensitivity 80%, specificity 94%, positive predictive value 77%, and negative predictive value 95%) than CTCA alone (77, 77, 46, and 93%, respectively; fusion vs. CTCA: specificity P=0.0002, positive predictive value P=0.0001).
Fusion images obtained with a general-purpose application were superior to CTCA images alone for detecting hemodynamically significant CAD.
Nuclear Medicine Communications 01/2012; 33(1):60-8. · 1.40 Impact Factor
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ABSTRACT: Initiating and weaning procedure of noninvasive positive pressure ventilation (NIPPV) on acute cardiogenic pulmonary edema (ACPE) has been determined empirically, and the total time of its use has been sometimes prolonged unnecessarily. A simple protocol for its use may facilitate initiation and avoids prolongation of the NIPPV treatment. We designed a step-wise protocol for NIPPV use and retrospectively examined the clinical outcome of our protocol for initiation and weaning of NIPPV in 45 patients with ACPE. Almost all patients recovered from respiratory distress successfully. There was no intubation nor complication related to NIPPV. In most of the cases, maximal-end expiratory pressure was less than 7-cm H2O. The mean duration of NIPPV was 19.5±28.0 h and the median duration was 8.0 h (interquartile range=14.0 h). This simple step-wise NIPPV protocol for ACPE can facilitate quick and safe initiation and termination of the treatment.
European journal of emergency medicine: official journal of the European Society for Emergency Medicine 08/2011; 19(4):267-70. · 0.73 Impact Factor
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ABSTRACT: BACKGROUND: Electrical isolation of the pulmonary veins (PV) is crucial for atrial fibrillation (AF) ablation. Conduction gaps on the circumferential PV antrum ablation (CPVA) line sometimes remain, which are sometimes difficult to identify. Methods and Results: CPVA of the ipsilateral superior and inferior PVs was performed during sinus rhythm or coronary sinus pacing using the NavX system in 22 AF patients, in whom 1 round of CPVA failed to disconnect 26 individual PVs (30%) in 18 patients. In these patients, a local activation map within the CPVA line (PV map) was created by a 20-pole circular mapping catheter with the use of the NavX, with 71 ± 37 sampling points per PV antrum. The conduction gap was defined as a site on the CPVA line, from which the activation proceeded toward the entire PV. The mapped PV antra were comprised of the left superior PV in 11, right superior PV in 10, left inferior PV in 3, right inferior PV in 1 and a left common PV in 1 PV(s). The conduction gaps were identified at 1.4 ± 0.7 sites per PV antrum, with an electrogram amplitude of 0.8 ± 0.7 mV. A point ablation at the gap completely isolated 24 out of 26 PV antra (92%) with 1.9 ± 1.3 applications. Conclusions: The PV map was useful for quickly and accurately identifying the conduction gap(s) after 1 round of CPVA.
Circulation Journal 07/2011; 75(10):2363-71. · 3.77 Impact Factor
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ABSTRACT: The L/N-type calcium channel blocker cilnidipine has unique effects including sympathetic nerve suppression and the balanced vasodilatation of arteries and veins that may alleviate morning hypertension (MHT) or peripheral edema caused by calcium channel antagonists. We used ambulatory blood pressure monitoring (ABPM) and a unique peripheral edema measurement to evaluate the effect of morning and bedtime cilnidipine in patients with MHT. Forty-three patients with MHT (60 ± 12 years) were randomly assigned to a morning or bedtime cilnidipine (10-20 mg/day). MHT was defined as a mean systolic blood pressure (SBP) ≥ 135 mm Hg by ABPM within 2 hours after awaking. After 3 months, greater SBP reductions were observed in the bedtime administration group (versus the morning administration group) at 3:30-6:00 AM (-24 ± 20 mm Hg vs. -10 ± 4 mm Hg; P < .05) and at 6:30-9:00 AM (-26 ± 15 mm Hg vs. -14 ± 17 mm Hg; P < .05). Although physical examinations showed leg edema in 16% of the patients, quantitative evaluations did not reveal significant volume gains. Cilnidipine had a greater effect on MHT, without causing significant leg edema, when administered at bedtime.
Journal of the American Society of Hypertension 06/2011; 5(5):410-6. · 2.12 Impact Factor
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ABSTRACT: EnSite array (EA) provides virtual activation of ventricular tachycardia (VT) and premature ventricular contraction (PVC) on a beat-to-beat basis.
Fifty-five consecutive patients (age 52+/-16 years) with 79 VTs/PVCs undergoing EA-guided radiofrequency catheter ablation (RFA) were studied, of whom 7 patients had organic heart diseases. A virtual activation map showed that 66 VTs/PVCs originated from the right ventricle (RV), including the RV outflow tract in 57, lateral wall of RV in 4, His bundle region in 3 and tricuspid annulus in 2. Ten VTs/PVCs originated from the left ventricle (LV), including the LV endocardium in 7 and aortic sinus cusp in 3. The origins of 3 PVCs, one each in 3 patients, were not identified. Six of 38 VTs were sustained and the remaining 32 VTs were non-sustained. RFA eliminated all but 3 focal PVCs, and all macroreentrant VTs at a critical conducting pathway, which was identified by the combined use of contact voltage and virtual activation maps. There were 11+/-9 applications, and the radiofrequency energy and fluoroscopy time were 11,354+/-13,360 J and 30+/-21 min, respectively. All patients with acute success were free of any symptoms during a follow up of 21+/-11 months.
EA-guided RFA is safe and effective for VT/PVC, irrespective of its origin, mechanism, sustainability, hemodynamic condition, and underlying heart disease.
Circulation Journal 05/2010; 74(7):1322-31. · 3.77 Impact Factor
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ABSTRACT: Complex fractionated atrial electrogram (CFAE) has been reported to relate to maintain atrial fibrillation (AF). The aims of this study were to investigate the relationship between CFAE and background conditions during sinus rhythm (SR).
Electroanatomical mapping using an EnSite Array was performed in 20 patients (paroxysmal AF:persistent AF = 16:4) who underwent pulmonary vein antrum isolation (PVAI). Contact bipolar electrograms were recorded before PVAI, during SR, and subsequently during induced AF. Peak-to-peak voltages and morphologies of the electrograms during SR were compared between sites with and without CFAE during AF. Among 1947 points obtained during SR, 974 (50%) were included in CFAE sites and 973 (50%) in non-CFAE sites. Electrogram amplitude during SR was higher at the CFAE sites than at the non-CFAE sites (2.4 +/- 1.7 vs. 1.9 +/- 1.9 mV; P < 0.0001), whereas fractionated or double electrograms were found in a similar range between the two areas (2 vs. 3%; P = 0.21). When analysed further in terms of AF termination by PVAI followed by confirmation of non-inducibility, the voltage of electrograms at the CFAE sites was lower (2.1 +/- 1.7 vs. 2.6 +/- 1.8 mV; P = 0.0001) and the morphology was more complex in patients without AF termination compared with those with AF termination.
Our results suggest that in paroxysmal and persistent AF with minimally damaged LA, the CFAE sites in patients with AF termination by PVAI alone represent healthy atrial tissue with rapid electrical activity in response to an AF driver located in the pulmonary vein. However, in patients without AF termination, they represent more damaged tissue responsible for maintaining AF.
Europace 02/2010; 12(4):494-501. · 1.98 Impact Factor
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ABSTRACT: It is unclear how the amplitude of bipolar electrogram relates to the local conduction velocity (CV) in patients with atrial fibrillation (AF). For 50 AF patients (paroxysmal/persistent AF: 40/10 patients), contact bipolar voltage maps of the left atrium (LA) were constructed during sinus rhythm using EnSite version 6.0J in a point-by-point recording fashion. Patients were divided into Groups A (n = 16), B (n = 19), and C (n = 15) according to the level of the lowest electrogram amplitudes: <0.5, 0.5-0.75, and 0.75-1.0 mV, respectively. Low-voltage zone (LVZ) was defined separately for these groups as a bipolar electrogram amplitude of <0.5, 0.5-0.75, and 0.75-1.0 mV, respectively. The local CV through the LVZ and non-LVZ was calculated along the direction of local activation within each zone for all groups.
Low-voltage zone was consistently found at the septal, anterior, and posterior LA in all groups. In Group A, CV through the LVZ was significantly slower compared with the non-LVZ (0.8 +/- 0.5 vs. 1.4 +/- 0.6 m/s, P = 0.004), but those through the LVZ and non-LVZ were similar in Group B (1.2 +/- 0.5 vs. 1.3 +/- 0.5 m/s, P = 0.07) and Group C (1.5 +/- 0.5 vs. 1.4 +/- 0.6 m/s, P = 0.79). The percentage of points showing fractionated or double potentials in the LVZ was significantly more in Group A (76/293 points, 26%) than in Group B (11/185 points, 6%), and Group C (7/135 points, 5%) (P < 0.0001 and P < 0.0001, respectively).
There was a significant slowing of local conduction in the LVZ defined as <0.5 mV and was frequently associated with fractionated or double potentials in patients with AF.
Europace 11/2009; 11(12):1597-605. · 1.98 Impact Factor
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Circulation Journal 09/2009; 73(8):1361-2. · 3.77 Impact Factor
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ABSTRACT: One of the serious complications of blood donation is vasovagal reaction (VVR) with syncope. This study was performed to determine if the measurement of hemodynamic responses to standing before blood collection (BC) was useful to identify the high-risk donors for VVR and also examined the effect of 300 mL of water ingestion in the prevention of VVR.
Blood pressure and heart rate (HR) during 5 minutes of standing were examined before and after BC in 93 donors. Because HR increase of 6 of 7 donors who developed syncopal VVR during standing after BC was 15 beats per minute (bpm) or greater, those with HR increase of 15 bpm or greater were determined as high-risk donors (n = 31). In another group (n = 117), 45 donors were identified as high risk based on the HR response before BC (15 bpm). The effect of 300 mL of water ingestion 15 minutes before BC on hemodynamic responses to standing and the rate of VVR after BC were analyzed.
Water ingestion given to the high-risk donors of the second group reduced HR increase with standing before BC (-6.6 ± 13.6 bpm, p < 0.02 vs. HR increase before water ingestion) and significantly suppressed VVR rate (2 of 45 donors with high risk, 4.4%,p < 0.04 vs. the first group; 6 of 31 high-risk donors, 19.4%).
HR response to standing before BC may detect the high-risk donors for VVR. For the high-risk donors, 300 mL of water ingestion may be a simple and effective way of prevention against syncopal VVR.
Transfusion 04/2009; 49(8):1630-6. · 3.22 Impact Factor
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ABSTRACT: Recognizing the relative location of the esophagus to the left atrial posterior wall (LAPW) is required to avoid esophageal injury during atrial fibrillation ablation.
The 24 patients undergoing circumferential pulmonary vein isolation (CPVI) each had the geometry of their left atrium (LA) and esophagus constructed by a noncontact mapping system with EnSite version 6.0J. The esophageal course relative to the LAPW was found to be to the left in 12, middle in 8, right in 2, and obliquely left-to-right in 2 patients, and in 13 patients (54%) it was located on or near either the left or right CPVI line. The mean distance between the esophagus and LAPW was shorter at the bottom line of the LAPW connecting both inferior pulmonary veins (3 +/- 3 mm) than at the LA roof line connecting both superior pulmonary veins (6 +/- 6 mm, P<0.01).
The location of the esophagus relative to the LAPW varies with the patient, but a close location to either CPVI line was found in approximately 50% and a close location between the esophagus and LAPW was found in the inferior and middle locations in most patients.
Circulation Journal 03/2009; 73(5):826-32. · 3.77 Impact Factor
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Journal of Arrhythmia 01/2009; 25(1):42-48.
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ABSTRACT: Though complex sleep apnea syndrome (compSAS) has recently been recognized as a new category of sleep apnea syndrome, its prevalence has not been determined, especially in Japan. Hence, we surveyed the prevalence of compSAS in Japan from the data of 4582 patients at eight sleep institutes who were diagnosed with obstructive SAS (apnea–hypopnea index [AHI] > 20). Using Morgenthaler's criteria we diagnosed as compSAS in 194 patients with a larger proportion of cardiac patients than in all titrated patients. Thus, the prevalence of compSAS in Japan was estimated to be 4.2%. We concluded that compSAS is an interesting condition but is not frequently found in Japan.
Sleep and Biological Rhythms 07/2008; 6(3):190 - 192. · 0.48 Impact Factor
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ABSTRACT: A case of extensive inferior myocardial infarction complicated by a large ventricular aneurysm is presented. Magnetic resonance (MR) imaging 4 days after the onset showed a small protrusion from the necrotic inferior myocardium, which expanded 10 days after onset with a marked pericardial effusion. The follow-up examination by MR and CT imaging 6 months after the onset revealed a large ventricular aneurysm from the inferior cardiac wall. After the aneurysmectomy, the histological study revealed that the aneurysm wall was made up of 2 different types of walls; the peripheral part was a false-pseudo aneurysm and the central part was a pseudo aneurysm. From the serial MR imaging, it is considered that such an aneurysm is primarily formed from a small discontinuation of the LV wall followed by oozing type rupture. Finally, the ruptured central part of the LV wall, which was covered by the pericardium, formed a pseudo aneurysm and the stretched peripheral area, which contains myocardium, formed a false-pseudo aneurysm afterward and then they extended together. Thus, MR imaging provided the important information for the understanding of the formation process of the pseudo and false pseudo LV aneurysm.
Internal Medicine 02/2007; 46(4):181-5. · 0.94 Impact Factor
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Journal of Cardiac Failure - J CARD FAIL. 01/2005; 11(9).
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ABSTRACT: It is now well known that sympathetic nerve discharges (SND) of animals as well as humans oscillate at low frequencies. To determine effects of the oscillation or burst on vasoconstriction, we applied two different kinds of electrical stimulation of the lumbar sympathetic nerve, and examined the magnitude and rate of vasoconstriction in the autoperfused hindquarter of α-chloralose anesthetized rabbits (n = 6). In the first protocol, we obtained power spectra of lumbar SND of rabbits with sinoaortic denervation and vagotomy. The power resided over the frequency range of 0.5–5 Hz with a broad peak at 1 Hz. In the second protocol, we modulated the basal stimulus trains 5 Hz on an average with slower rhythms of 0.5, 1.0 and 2.0 Hz (frequency modulation). This experiment revealed that, compared with the results with constant stimulation, the frequency modulation of stimulation did not affect the magnitude of the maximal vasoconstriction but augmented the rate of vasoconstriction at 0.5 and 1.0 Hz (P < 0.01). In the third protocol, we examined effects of stimulation on vasoconstriction while changing the intra-burst frequency at a fixed inter-burst interval. Since the power spectra of lumbar SND showed a peak at 1 Hz in the first protocol, we fixed the inter-burst interval at 1 Hz and varied the intra-burst frequency at 10, 20, and 40 Hz while the total number of stimuli were kept constant at 5 impulses per second. This experiment showed that the 10 Hz burst was most effective in augmenting the rate of vasoconstriction, though the magnitude of maximal vasoconstriction was not affected by any of them. These results may suggest that oscillation and burst of SND may work as an accelerator of vasoconstriction in resistance vessels.
Journal of the Autonomic Nervous System.
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ABSTRACT: It has been shown that central transduction of the input from arterial baroreceptors shows bandpass characteristics. Previous studies have demonstrated that anesthesia may affect the gain of arterial baroreflex control of sympathetic nerve activity, but whether anesthesia affects the frequency response of central transduction of the arterial baroreflex system is not known.We examined cardiac cycle-related oscillation of renal sympathetic nerve activity (RNA) in conscious (n = 5) and α-chloralose-anesthetized (n = 10) rabbits. Power spectra of arterial pressure and RNA were obtained at rest, after i.v. propranolol and after i.v. isoproterenol. At rest with a cardiac cycle at about 5 Hz, cardiac cycle-related oscillation of RNA was observed in conscious rabbits, but it was not present or markedly attenuated in anesthetized rabbits. As the cardiac cycle was slowed by propranolol in anesthetized rabbits, cardiac cycle-related oscillation of RNA gradually appeared. These results suggest that α-chloralose anesthesia in rabbits narrowed the bandpass region of the central baroreflex system so that the baroreceptor input at a high frequency (above 5 Hz) was no longer transduced into RNA.
Journal of the Autonomic Nervous System.
