Arrhythmogen jobb kamrai dysplasia – a terheléses vizsgálat prognosztikai jelentősége panaszmentes egyénben = Arrhytmogenic right ventricle – prognostic significance of exercise test

A szerzők áttekintik az arrhythmogen jobb kamrai cardiomyopathia/dysplasia témakörével kapcsolatos legfontosabb ismereteket. Igazolt arrhythmogen jobb kamrai cardiomyopathia/dysplasia esetén – tünetmentes egyénekben – a terheléses vizsgálat során észlelt kamrai tachycardia prognosztikus jelentőségéről nem rendelkezünk adatokkal. A szerzők közleményükben egy 25 éves nőbeteg esetét ismertetik, akinél bokasérülés ellátása kapcsán észleltek kóros EKG-t és emiatt küldték kardiológiai vizsgálatra. A fizikális vizsgálat kóros eltérést nem mutatott, az EKG-felvételen normális sinusrhythmus és bal tengelyállás mellett a II, III, aVF- és V2-V6 elvezetésekben negatív T-hullám látszott. A mellkasröntgen és a laboratóriumi vizsgálatok kóros eltérést nem igazoltak. Az echokardiográfia normális bal kamrai ejekciós frakció mellett inferior akinesist és tágabb jobb kamrát igazolt. A terheléses vizsgálat során a beteg 9 MET-et teljesített, a terhelés során előbb sporadikus kamrai extrasystolia, majd 3 percig tartó kamrai tachycardia jelentkezett, amely a terhelés megszakítása és hasprés alkalmazására megszűnt. A szív-MR-vizsgálat normális balkamra-méreteket, falmozgást és ejekciós frakciót igazolt. Az emelkedett jobb kamrai végszisztolés és végdiasztolés volumen mellett a jobb kamrai ejekciós frakció jelentősen csökkent (31,6%), és a jobb kamrának megfelelően akinetikus területek ábrázolódtak. Késői típusú kontraszthalmozódás a bal kamrában nem igazolódott, a vékony falú jobb kamra fala e tekintetben pontosan nem volt megítélhető. Az EKG- és a CMR-eltérések alapján arrhythmogen jobb kamrai cardiomyopathia/dysplasia diagnózisát állították fel. Tekintettel arra, hogy a beteg panaszmentes volt és a családban hirtelen halál nem fordult elő, preventív célzattal gyógyszeres kezelés és/vagy ICD-implantáció nem történt. Három hónappal később a beteg hirtelen meghalt. A sectio jelentősen tág jobb kamrát igazolt, a jobb kamra fala elvékonyodott, amelyben jellegzetes lokalizációban (beáramlási és kiáramlási traktus, valamint a csúcs) az izomszövet helyett felszaporodott zsírszövet volt látható. Az érintett jobb kamra falában a Mallory-féle foszfor-volfrám savas hematoxilinfestéssel fibrosist is igazolni lehetett. A szerzők azt a következtetést vonják le, hogy tünetmentes betegben, igazolt arrhythmogen jobb kamrai cardiomyopathia/dysplasia esetén a terheléses EKG-vizsgálat során provokált kamrai tachycardia rossz prognosztikai jel, és ilyen esetben ICD-implantáció indokolt lehet. Orv. Hetil., 2010, 151, 2145–2149. | The authors summarize the present knowledge on arrhythmogenic right ventricular cardiomyopathy/dysplasia. Limited data are available about natural history of asymptomatic patients with arrhythmogenic right ventricle cardiomyopathy/dysplasia, who have a ventricular tachycardia during exercise test. A 25-year old female patient was treated with osteosynthesis because of ankle injury. Cardiology consultation was performed because of an abnormal ECG. Physical examination was normal. ECG showed a normal sinus rhythm, left axis deviation, negative T waves in leads II, III, aVF and V2-V6. Chest X-ray and laboratory findings were normal. Echocardiography showed normal left ventricular ejection fraction along with inferior akinesis and dilated right ventricle. Bicycle exercise test revealed a good exercise tolerability (9 MET), and after sporadic ventricular extra systoles ventricular tachycardia developed lasting for 3 minutes, which spontaneously stopped after aborting the test and performed abdominal strain. MRI was performed which has shown normal left ventricular size, wall motion and ejection fraction and depressed right ventricle function (ejection fraction 31.6%) enlarged right ventricular end-systolic and diastolic volumes, hypo-akinetic regions without aneurysm and bulging. No contrast enhancement was seen in the thin right ventricular wall. According to abnormal ECG and MRI findings arrhythmogenic right ventricle cardiomyopathy/dysplasia was diagnosed. No ICD implantation was indicated because the patient was asymptomatic, and no sudden cardiac death occurred in the family. Three month later the patient was found dead. At autopsy the right ventricular chamber was markedly enlarged, with multiple translucent areas of fatty accumulation accompanied with extended myocytes loss. There was a characteristic triangle dysplasia: the inflow, outflow tracts and apical areas. The coronaries were free of atherosclerosis. Mallory’s phosphotungstic acid-hematoxilin stain demonstrated the presence of fibrosis within the scattered myocardium. Conclusion: malignant ventricular arrhythmia provoked by exercise test in an asymptomatic arrhythmogenic right ventricle cardiomyopathy/dysplasia patient with negative family history should be an indication for ICD implantation. Orv. Hetil., 2010, 151, 2145–2149

Radiofrequency Ablation at Low Irrigation Flow Rates Using a Novel 12-Hole Gold Open-Irrigation Catheter

BACKGROUND: High irrigation rates during radiofrequency (RF) ablation may cause fluid overload and limit lesion size. This in vivo animal study assessed the safety and efficacy of RF ablation at low irrigation rates using a novel 12-hole gold catheter. METHODS: A total of 103 lesions, created on the thigh of five mongrel dogs, were analyzed. Lesions were created using a 12-hole irrigated gold-tip (Au) and a six-hole irrigated platinum-iridium (PtIr) catheter (both 7F/3.5-mm electrode; BIOTRONIK SE & CO, KG, Berlin, Germany) in parallel and perpendicular orientation. RF current was delivered for 60 seconds at 30 W using 8 mL/min and 15 mL/min irrigation. Electrode temperature, steam pops, lesion dimensions, and coagulum formation were recorded. RESULTS: Electrode temperatures were lower for Au compared to PtIr in parallel (8 mL/min: 38.1 +/- 1.7 degrees C vs 48.0 +/- 4.8 degrees C, P < 0.0001; 15 mL/min: 36.0 +/- 1.5 degrees C vs 46.9 +/- 5.4 degrees C, P < 0.0001) and perpendicular position (15 mL/min: 35.5 +/- 1.2 degrees C vs 38.4 +/- 2.5 degrees C, P = 0.003). The number of steam pops between Au and PtIr was comparable for parallel (8 mL/min: 14% vs 27%, P = 0.65; 15 mL/min: 14% vs 43%, P = 0.21) and perpendicular orientation (8 mL/min: 25% vs 17%, P = 1.00; 15 mL/min: 18% vs 0%, P = 0.48). Au created larger volumes than PtIr at 8 mL/min irrigation (861 +/- 251 mm3 vs 504 +/- 212 mm3 , P = 0.004); however, for 15 mL/min, volumes were comparable (624 +/- 269 mm3 vs 768 +/- 466 mm3 , P = 0.46). No coagulum formation was observed for any of the catheters on the surface and catheter tip. CONCLUSION: RF ablation at low flow rate using a novel 12-hole irrigation Au catheter is safe and results in larger lesions than with a PtIr electrode

High-volume lesions using a new second-generation open irrigation radiofrequency catheter are associated with the development of inhomogeneous lesions

BACKGROUND: After catheter ablation there is often a discrepancy between acute and chronic success rates. We aimed to evaluate major determinants for lesion quality and understand different manifestations of lesion structures. METHODS: In a canine thigh muscle model radiofrequency (RF) current was delivered for 60 seconds at 30 W (n = 39) or 50 W (n = 18) with 15-g contact force. A second-generation 12-hole gold open irrigation catheter (SGIT) and a first-generation six-hole platinum-iridium catheter (FGIT; Biotronik, Berlin, Germany) were used. Electrode and tissue temperatures (at the surface and 3.5-mm and 7-mm depth) were recorded and lesion dimensions were measured. Lesions with steam pops were excluded. Histological examination was performed to evaluate homogeneity of the lesions. Inhomogeneity was defined as a visual multiband lesion pattern indicating different histological characteristics. RESULTS: In total 57 lesions were created. Seventeen lesions were excluded (steam pops) and 40 lesions were analyzed. A total number of 11 homogeneous and 29 inhomogeneous lesions were identified. Using the SGIT catheter 16.7% of the lesions was homogeneous and 83.3% inhomogeneous; for FGIT it was 43.8% and 56.2% (P = 0.065), respectively. Homogeneous lesions had lower volumes as compared to inhomogeneous lesions (514.0 +/- 198.8 vs 914.8 +/- 399.1 mm, P = 0.003). Multiple logistic regression analysis indicated that the SGIT catheter is a significant predictor for inhomogeneous lesions (odds ratio 6.5, 95% confidence interval 1.1-38.8; P = 0.040) independent from power setting and flow rate. CONCLUSIONS: The development of inhomogeneous lesions after acute RF ablation is associated with higher lesion volumes and the use of the second-generation irrigation gold-tip catheter

Spontán aortaruptura várandósság alatt = Spontaneous aortic rupture during pregnancy

Az aortadissectio ritka kórkép. A 40 évnél fiatalabb nőkben kialakuló aortadissectiók 50%-a várandósság alatt jelentkezik. A szerzők közleményükben a terhesség harmadik trimeszterében járó multipara esetét ismertetik, akinél hirtelen halál következett be, amelynek hátterében az aorta ascendens rupturáját igazolta a boncolás. Az esetet érdekessé teszi, hogy a beteg családjában már előfordult hasonló megbetegedés. A szerzők ismertetik a tüneteket, a háttérben álló esetleges genetikai eltéréseket és áttekintik a nemzetközi irodalomban előforduló hasonló eseteket is. Orv. Hetil., 2011, 152, 929–933. | Aortic dissection is a rare entity. Half of the aortic dissection cases occur during pregnancy in women under the age of 40. The authors report a case of a multiparous woman at the third trimester of her sixth pregnancy, who died from a sudden and intractable cardiovascular shock. Autopsy revealed the dissection of the ascending aorta. The case is interesting, especially because in the pregnant woman’s family it was not the first sudden death during pregnancy. Authors review the relevant literature regarding the symptoms and the genetic basis of this rare but potentially lethal complication of pregnancy. Orv. Hetil., 2011, 152, 929–933

Víruskimutatás molekuláris biológiai vizsgálattal cardiomyopathiás betegek szívizommintáiból = Molecular biological virus identification in dilated cardiomyopathy

Régóta ismert, hogy főként az enterovírusok, azok közül is a Coxsackie-B3 játszik elsődleges szerepet a szívizomgyulladás patomechanizmusában, továbbá az annak lehetséges következményeként kialakuló dilatativ cardiomyopathiában. Célkitűzés: Jelen vizsgálatainkban ezeknek a vírusoknak feltételezett kóroki szerepét kívántuk kimutatni szívátültetésen átesett dilatativ cardiomyopathiás betegekben. Módszer: A víruskimutatás e betegek explantált szívizommintáiból történt. A szív öt különböző, előre meghatározott régióiból ún. nested polimeráz láncreakciót alkalmazva sokszoroztuk az Adenovírus-3, Humán herpeszvírus-6 típus és az enterovírus konzervatív régióit. Eredmények: Az eddig vizsgált 14 beteg mintáiból 3 esetben kaptunk Adenovírus-3-ra pozitív eredményt, melyet a későbbi szekvenálás is alátámasztott. További egy esetben az Adenovírus-3 mellett Humán herpeszvírus-6 típus szekvenciát is találtunk. Enterovírus genomot azonban nem sikerült detektálnunk egyik beteg mintájában sem. Következtetés: Vizsgálataink során adenovírus-genom fordult elő a leggyakrabban a vizsgált betegcsoportban. A kimutatott vírusszekvenciák egy korábban lezajlott vírusfertőzésre utalnak, mely hozzájárulhatott a dilatativ cardiomyopathia kialakulásához. A különböző víruspartikulumok molekuláris biológiai módszerrel szívizomból történő kimutatása segítséget nyújthat a betegség hatékony és költségkímélő kezelésében. Enteroviruses have been considered to be the most common cause of acute myocarditis and possible consequence of dilated cardiomyopathy. Some publications shed light to the role of other viruses in this disease as well. Our molecular investigation has demonstrated that adeno- and herpes viruses might also frequently occur in dilated cardiomyopathy. Aim: The aim of our study was to screen virus genomes in heart tissues from heart-transplanted patients to prove their possible role in the pathogenesis of dilated cardiomyopathy. Methods: DNA and RNA were isolated from five regions of the heart muscle. Amplification for Adenovirus Type 3, Human Herpes Virus Type 6 and Enterovirus genomes were performed by nested-Polymerase Chain Reaction. Finally the virus-positive samples were direct sequenced. Results: In 2 patients Adenovirus Type 3 and in 1 patient both Adenovirus Type 3 and Human Herpes Virus Type 6 were detected. No enteroviruses were found in any heart tissue. Conclusions: In our study the adenovirus genome was found to be the most frequent virus genome in explanted heart tissues. The identified viral sequences proved previous viral infection, which could have played a role in the development of dilated cardiomyopathy. Detection of different viruses in the myocardium by molecular biological examinations might contribute to adequate treatment of these patients

Spontán aortaruptura várandósság alatt [Spontaneous aortic rupture during pregnancy]

Aortic dissection is a rare entity. Half of the aortic dissection cases occur during pregnancy in women under the age of 40. The authors report a case of a multiparous woman at the third trimester of her sixth pregnancy, who died from a sudden and intractable cardiovascular shock. Autopsy revealed the dissection of the ascending aorta. The case is interesting, especially because in the pregnant woman's family it was not the first sudden death during pregnancy. Authors review the relevant literature regarding the symptoms and the genetic basis of this rare but potentially lethal complication of pregnancy

Comparative study on cardiotoxic effect of Tinuvin 770: A light stabilizer of medical plastics in rat model

Tinuvin 770 [bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate], is a UV light stabilizer plastic additive used worldwide. It is a component of many plastic materials used in medical and food industries. Earlier studies demonstrated its in vitro L-type Ca2+ channel and nicotinic acetylcholine receptor blocking properties. Our previous experiments have proved the toxic effects of Tinuvin 770 on isolated rat cardiomyocytes. The present study investigates the cardiotoxic effects of Tinuvin 770 in vivo. Wistar rats were intraperitoneally injected with increasing doses of Tinuvin 770 (1, 10, 100 microg, and 1 mg) 15 times during a 5-week period. Myocardial samples were analyzed by light, electron, and fluorescent microscopy. The lead-acetate method was used to detect intracellular Ca2+, and glyoxylic acid technique to assess alteration in adrenergic innervation. Focal myocytolysis and hypercontraction necrosis could be observed in rats treated with higher doses of Tinuvin 770. In these groups, intracellular Ca2+ accumulation and increased catecholamine release were detected. Tinuvin 770 not only displays L-type Ca2+ channel blocking properties, but can also lead to catecholamine release, similar to effects of the first generation of L-type Ca2+ channel blockers. Morphological results correspond to catecholamine-induced myocardial damage. Current literature, as well as our study, indicates that more detailed toxicological analysis of Tinuvin 770 should be required, and current regulations in medical and food industries should adopt the new results

No mutation but high mRNA expression of Coxsackie-Adenovirus Receptor was observed in both dilated and ischemic cardiomyopathy

The most common causes of acute myocarditis and the possible consequence of dilated cardiomyopathy are virus infections. The receptor of the two most common viruses connected to these myocardial diseases was identified as Coxsackie-Adenovirus Receptor. The purpose of this study was to assess Coxsackie-Adenovirus Receptor mRNA expression in the myocardium and search for mutations in the Coxsackie-Adenovirus Receptor gene to compare dilated, inflammatory and ischemic cardiomyopathy with control group. All the myocardial samples were obtained from 35 explanted hearts during heart transplantation, than DNA and RNA were isolated from the muscle samples. cDNA was generated from RNA using reverse transcription, and real-time PCR was performed with relative quantification by beta-actin gene as endogenous control. Using DNA extracted from the myocardial samples, we sequenced all the seven exons of the Coxsackie-Adenovirus Receptor gene. Coxsackie-Adenovirus Receptor mRNA expression was higher in both ischemic and dilated cardiomyopathy groups than in inflammatory cardiomyopathy and healthy control groups. Sequencing of CAR gene showed no sign of mutation. Therefore, the sequences result of CAR exons did not show any mutation or polymorphism, that explains a determinant role of CAR in dilated or ischemic CM. Our results suggest that high mRNA expression of Coxsackie-Adenovirus Receptor may support its role in regeneration of the damaged myocardium rather than having any role in viral mediated heart disease