Prenatal cardiology

Prirođene srčane grješke uzrokom su 7 % svih novorođenačkih smrti. Većina tih smrti događa se kod neliječene djece. Fetalna ehokardiografija omogućava rano otkrivanje prirođenih srčanih grješaka što omogućava i istovremeno liječenje PSG intrautero ili u ranoj neonatalnoj dobi. Cilj ovog istraživanja jest istražiti vrijednost fetalne ehokardiografije u poboljšanju prenatalnog otkrivanja PSG. Ovo retrospektivno kohortno istraživanje je rađeno na uzorku od 1380 trudnica, upućenih od ginekologa, koje su pregledane u Fetalnoj kardiološkoj ambulanti KBC-a Zagreb u razdoblju od 1.1.2012.do 1.1.2015. Učinjen je ukupno 2001 pregled zato što su neke trudnice pregledane 2 i više puta, iz čega vidimo godišnji prosjek od 600 do 670 pregleda. Većinu indikacija određivali su opstetričari, manji dio je upućen od strane reumatologa, genetičara ili drugih subspecijalista dok je dio trudnica tražilo pregled rutinski prema vlastitoj želji. U 14.2% trudnica postavljena je sumnja na srčanu bolest (197/1380) od kojih su najčešće bile: VSD 25%, AVS 6.12% , CMP 10.7%, aritmije 14.78%, CoA 8.16%, BAV 3.02% te složene PSG 15.28%. Patološki nalaz je puno češći kod žena koje su poslane na pregled s određenom indikacijom, nego kod onih koje su poslane na rutinski pregled. Od ovih 197 djece, njih 84 je nakon rođenja praćeno u našoj klinici pri čemu je ispravno postavljena prenatalna dijagnoza kod 45 djece što pokazuje osjetljivost testa od 53%. Iz ovih rezultata dolazimo do zaključka da bi se trudnicama s GD i aritmijama kao propisanim indikacijama trebala raditi prenatalna ehokardiografija radi detekcije PSG, slično ostalim istraživanjima na ovom području, u preko 50% slučajeva ultrazvukom je pravilno postavljena dijagnoza. Iz toga zaključujemo da je fetalna ehokardiografija korisna metoda u detekciji PSG što omogućava ranu intervenciju i liječenje grješaka.Complex heart malformations cause congenital heart disease (CHD) responsible for 7% of all deaths in newborns. Most of these deaths occur in untreated children. Fetal echocardiography (FE) enables early detection of CHD, allowing for early intervention. The aim of this study was to determine the value of the FE in improvement of prenatal detection of CHD. This retrospective cohort study involved 1380 pregnant women examined in the Fetal cardiology clinic in the University hospital Zagreb between 1st January 2012 and 1st January 2015, after being referred by their obstetrician. Women were examined on 2001 examination which shows us the annual number of examinations that goes from 600 to 670 examinations. Most of the women were sent by their obstetricians, some were sent by geneticists, internists and other subspecialists while smaller number of women were examined on their own request. The incidence of CHD in this study equaled 14.2%, 197 sick child form 1380 examined children. The most common CHD were: VSD 25%, complex CHD 15.28%, AVS 6.12% , CMP 10.7%, arrhythmia 14.78%, CoA 8.16% and BAV 3.02%. CHD were more common in children whose mothers were sent onan examination because of the specific indications then in children whose mothers were examined as a routine examination. 84 of 196 children with CHD detected by FE were examined in our clinic after birth. The diagnosis was confirmed in 45 of them, showing the sensitivity of FE scanning for CHD of 53%. In conclusion, only pregnant women with indications for FE should be scanned for CHD. Similarly to other studies in this field, over 50% percent of the cases of CHD were correctly identified by FE in this study. Therefore, we claim that FE is a useful method in determining CHD in fetuses, allowing for early intervention after birth

HE ROLE OF GESTATIONAL AGE AND NUMBER OF FE EXAMINATIONS IN IMPROVING DIAGNOSING OF FETAL CONGENITAL HEART DISEASE

Deskriptivno istraživanje: Utjecaj gestacijske dobi i broja pregleda fetalnom ehokardiografijom na poboljšano otkrivanje prirođenih srčanih bolesti kod fetusa. Prema literaturi, fetalna ehokardiografija (FE) ima najveću dijagnostičku osjetljivost za srčane bolesti fetusa između 22. i 24. tjedna gestacije. Osjetljivost pretrage ovisi o vremenu pretrage, iskustvu dijagnostičara, vrsti srčane bolesti i broju pregleda pojedine trudnice. Cilj našeg istraživanja jest odrediti najpogodnije vrijeme za FE respektirajući indikacijske smjernice te moguću potrebu za većim brojem pregleda radi povećanja senzitivnosti pretrage u prenatalnom otkrivanju srčanih bolesti. Želimo dati vlastiti doprinos povećanju senzitivnosti FE-a. Rezultati: Istraživanje je učinjeno na uzorku od 1380 trudnica koje su pregledane u Fetalnoj kardiološkoj ambulanti Kliničkoga bolničkog centra (KBC) Zagreb u razdoblju od 1. 1. 2012. do 1. 1. 2015. Učinjen je 2001 pregled (neke su trudnice pregledane 2 i više puta), što čini godišnji prosjek od 600 do 670 pregleda. Većinu indikacija određivali su opstetričari, manji dio uputili su reumatolozi, genetičari ili drugi supspecijalisti, dok je dio trudnica tražio pregled prema vlastitoj želji. Pozitivan nalaz PSG-a ili druge srčane bolesti imalo je 14,2% trudnica, odnosno 196 fetusa. Najveći broj grješaka u našem istraživanju otkriven je u indikacijskom razdoblju od 22. do 28. i od 32. do 36. gestacijskog tjedna (64 + 57 = 121 ili 61,7%). Kod većine je patološki nalaz utvrđen na prvom pregledu, a kod 27 trudnica (10,3%) na 2. ili 3. pregledu. Zaključak: U rizičnoj skupini trudnica FE bi trebalo prvi put raditi između 22. i 28. gestacijskog tjedna, a drugi put nakon navršenoga 32. tjedna gestacije. Da bismo postigli optimalnu senzitivnost pretrage, svaku trudnicu valjalo bi pregledati najmanje dva puta. Trudnice sa sistemskim bolestima vezivnog tkiva valja predložiti za FE prije navršenoga 15. tjedna trudnoće.Descriptive study: The role of gestational age and number of FE examinations in improving detection of congenital heart defects in newborns. According to the literature data, fetal echocardiography (FE) is highly sensitive in detecting congenital heart defects (CHDs) between 20 and 24 weeks of gestation. Its sensitivity depends on timing of the examination, diagnostician’s experience, type of CHD, and the number of examinations performed in a single pregnant woman. The aim of our study was to determine the best time for FE examination, as well as possible need for an increased number of examinations in order to improve sensitivity of prenatal diagnosing of CHD. We wish to give our own contribution to the increase of the FE sensitivity. Results: The study involved 1380 pregnant women examined in Fetal cardiology clinic in the University Hospital Centre Zagreb between 1st January 2012 and 1st January 2015. Since some pregnant women were examined two or more times, a total of 2001 examinations were performed, making an average of 600 to 670 examinations performed annually. Most of the indications for FE were determined by obstetricians, while some pregnant women were referred for FE by their rheumatologist, genetic medicine specialist, or physicians of other subspecialties. A few pregnant women were examined at their own request. CHD was diagnosed on FE examination in 14.2% of pregnant women, or rather 196 fetuses. The time window that CHD was most commonly diagnosed in ranged between 22 and 28, or 32 and 36 weeks of gestation (64 + 57 = 121 or 61.7%). Most of the CHDs were detected on the first FE examination, with 27 pregnant women (10.3%) diagnosed on the 2nd or the 3rd examination. Conclusion: The first FE examination should be performed in pregnant women with risk factors for CHD between 22 and 28 weeks of gestation, with a follow-up FE after 32 weeks of gestation. In order to improve the sensitivity of prenatal diagnosing of CHD each pregnant woman should be examined at least twice. Pregnant women with systemic connective tissue disease need to be proposed for FE before 15 weeks of gestation

Utjecaj gestacijske dobi i broja pregleda fetalnom ehokardiografijom na poboljšanu dijagnostiku prirođenih srčanih bolesti kod fetusa [The role of gestational age and number of fe examinations in improving diagnosing of fetal congenital heart disease]

Descriptive study: The role of gestational age and number of FE examinations in improving detection of congenital heart defects in newborns. According to the literature data, fetal echocardiography (FE) is highly sensitive in detecting congenital heart defects (CHDs) between 20 and 24 weeks of gestation. Its sensitivity depends on timing of the examination, diagnostician’s experience, type of CHD, and the number of examinations performed in a single pregnant woman. The aim of our study was to determine the best time for FE examination, as well as possible need for an increased number of examinations in order to improve sensitivity of prenatal diagnosing of CHD. We wish to give our own contribution to the increase of the FE sensitivity. Results: The study involved 1380 pregnant women examined in Fetal cardiology clinic in the University Hospital Centre Zagreb between 1st January 2012 and 1st January 2015. Since some pregnant women were examined two or more times, a total of 2001 examinations were performed, making an average of 600 to 670 examinations performed annually. Most of the indications for FE were determined by obstetricians, while some pregnant women were referred for FE by their rheumatologist, genetic medicine specialist, or physicians of other subspecialties. A few pregnant women were examined at their own request. CHD was diagnosed on FE examination in 14.2% of pregnant women, or rather 196 fetuses. The time window that CHD was most commonly diagnosed in ranged between 22 and 28, or 32 and 36 weeks of gestation (64 + 57 = 121 or 61.7%). Most of the CHDs were detected on the first FE examination, with 27 pregnant women (10.3%) diagnosed on the 2nd or the 3rd examination. Conclusion: The first FE examination should be performed in pregnant women with risk factors for CHD between 22 and 28 weeks of gestation, with a follow-up FE after 32 weeks of gestation. In order to improve the sensitivity of prenatal diagnosing of CHD each pregnant woman should be examined at least twice. Pregnant women with systemic connective tissue disease need to be proposed for FE before 15 weeks of gestation

INDICATION GUIDELINES FOR FETAL ECHOCARDIOGRAPHY AND THEIR INFLUENCE ON PRENATAL DIAGNOSIS OF A HEART DISEASE

Deskriptivno istraživanje: Indikacijske smjernice za fetalnu ehokardiografiju i njihov utjecaj na prenatalnu ­dijagnozu srčane bolesti. Cilj: Istražiti povezanost glavnih indikacija za fetalnu ehokardiografiju (FE) zbog kojih su trud­nice upućene na pregled s konačnim nalazom. Hipoteza: Prirođene srčane grješke (PSG) najčešće su prirođene anomalije koje se kod trudnica s određenim indikacijama, rizičnima za njihov nastanak, uspješno otkrivaju fetalnim ehokardiografskim pregledom. To omogućava njihovo rano zbrinjavanje, a time se smanjuju morbiditet i mortalitet novorođenčadi sa srčanim bolestima te se pozitivno utječe na krivulju perinatalnog mortaliteta. Pridržavanjem propisanih indikacija povećala bi se ukupna učinkovitost FE-a i smanjio broj negativnih nalaza. Rezultati: Istraživanje je rađeno na uzorku od 1374 trud­nice, odnosno 1380 trudnoća, koje su pregledane u Fetalnoj kardiološkoj ambulanti Kliničkoga bolničkog centra Zagreb u razdoblju od 3 godine (1. 1. 2012. do 1. 1. 2015.). Većinu indikacija određivali su opstetričari, dio su uputili reumatolozi, genetičari ili drugi supspecijalisti, dok je dio trudnica tražio pregled prema vlastitoj želji. Prenatalno je srčana bolest otkrivena u 14,2% pregledanih fetusa (196/1380) od čega: ventrikularni septalni defekt (VSD) u 25%, kompleksne PSG u 15,3%, aritmije u 14,79%, kardiomiopatije (KMP) u 10,71%, koarktacija aorte (CoA) u 7,65%, aortalna valvularna stenoza (AVS) u 6,12%, bikuspidalna aortalna valvula (BAV) u 3,06%, ostalo u 16,83%. Patološki je nalaz puno češći kod žena koje su poslane na pregled s propisanom određenom indikacijom nego u onih koje su došle na pregled rutinski ili prema vlastitoj želji. Zaključak: Fetalna ehokardiografija dijagnostički je najučinkovitija ako se pridržavamo propisanih indikacija koje pobuđuju sumnju na primarnu srčanu bolest (PSG u obitelji, aritmije, KMP), neke sindromne bolesti fetusa, dijabetes ­melitus ili gestacijski dijabetes te sistemske bolesti vezivnog tkiva majke (pozitivna specifična protutijela).Descriptive study: Fetal echocardiography indications and their role in the development of congenital heart defects in newborns. Hypothesis: Congenital heart defects (CHDs) are the most common birth defects diagnosed with the aid of fetal echocardiography (FE) in pregnant women with certain risk factors for CHD, enabling early treatment. Aim: of this study was to determine the connection between the indications which prompted physicians to refer pregnant women for FE and the CHDs caused by these indications. Results: The study involved 1374 pregnant women with 1380 pregnancies, referred by their primary gynecologist and examined in the Fetal cardiology clinic of theUniversityHospital Centre Zagreb, Croatia, between the 1st January 2012 and the 1st January 2015. Most indications for FE were determined by ­obstetricians, while some pregnant women were referred for FE by their rheumatologist, genetic medicine specialist or physicians of other subspecialties. A few pregnant women were examined at their own request. The incidence of CHD was 14.2% (196 fetuses were diagnosed out of 1380 examined), the most common being ventricular septal defect (25%), ­complex CHD (15.3%), arrhythmia (14.79%), cardiomyopathy (10.71%), coarctation of the aorta (7.65%), aortic valve stenosis (6.12%) and bicuspid aortic valve (3.06%). Pathology was more likely to be detected in pregnant women referred for FE with a specific indication, in comparison to those sent for a routine examination. Conclusion: Fetal echocardiography is diagnostically most efficient if we adhere to the prescribed indications which may indicate a primary heart disease (CHD in family, arrhythmias, CMP), fetal syndrome disease, diabetes mellitus or gestational diabetes, and systemic diseases of the mother’s linking tissue (positive specific antibodies)

INDICATION GUIDELINES FOR FETAL ECHOCARDIOGRAPHY AND THEIR INFLUENCE ON PRENATAL DIAGNOSIS OF A HEART DISEASE

Deskriptivno istraživanje: Indikacijske smjernice za fetalnu ehokardiografiju i njihov utjecaj na prenatalnu ­dijagnozu srčane bolesti. Cilj: Istražiti povezanost glavnih indikacija za fetalnu ehokardiografiju (FE) zbog kojih su trud­nice upućene na pregled s konačnim nalazom. Hipoteza: Prirođene srčane grješke (PSG) najčešće su prirođene anomalije koje se kod trudnica s određenim indikacijama, rizičnima za njihov nastanak, uspješno otkrivaju fetalnim ehokardiografskim pregledom. To omogućava njihovo rano zbrinjavanje, a time se smanjuju morbiditet i mortalitet novorođenčadi sa srčanim bolestima te se pozitivno utječe na krivulju perinatalnog mortaliteta. Pridržavanjem propisanih indikacija povećala bi se ukupna učinkovitost FE-a i smanjio broj negativnih nalaza. Rezultati: Istraživanje je rađeno na uzorku od 1374 trud­nice, odnosno 1380 trudnoća, koje su pregledane u Fetalnoj kardiološkoj ambulanti Kliničkoga bolničkog centra Zagreb u razdoblju od 3 godine (1. 1. 2012. do 1. 1. 2015.). Većinu indikacija određivali su opstetričari, dio su uputili reumatolozi, genetičari ili drugi supspecijalisti, dok je dio trudnica tražio pregled prema vlastitoj želji. Prenatalno je srčana bolest otkrivena u 14,2% pregledanih fetusa (196/1380) od čega: ventrikularni septalni defekt (VSD) u 25%, kompleksne PSG u 15,3%, aritmije u 14,79%, kardiomiopatije (KMP) u 10,71%, koarktacija aorte (CoA) u 7,65%, aortalna valvularna stenoza (AVS) u 6,12%, bikuspidalna aortalna valvula (BAV) u 3,06%, ostalo u 16,83%. Patološki je nalaz puno češći kod žena koje su poslane na pregled s propisanom određenom indikacijom nego u onih koje su došle na pregled rutinski ili prema vlastitoj želji. Zaključak: Fetalna ehokardiografija dijagnostički je najučinkovitija ako se pridržavamo propisanih indikacija koje pobuđuju sumnju na primarnu srčanu bolest (PSG u obitelji, aritmije, KMP), neke sindromne bolesti fetusa, dijabetes ­melitus ili gestacijski dijabetes te sistemske bolesti vezivnog tkiva majke (pozitivna specifična protutijela).Descriptive study: Fetal echocardiography indications and their role in the development of congenital heart defects in newborns. Hypothesis: Congenital heart defects (CHDs) are the most common birth defects diagnosed with the aid of fetal echocardiography (FE) in pregnant women with certain risk factors for CHD, enabling early treatment. Aim: of this study was to determine the connection between the indications which prompted physicians to refer pregnant women for FE and the CHDs caused by these indications. Results: The study involved 1374 pregnant women with 1380 pregnancies, referred by their primary gynecologist and examined in the Fetal cardiology clinic of theUniversityHospital Centre Zagreb, Croatia, between the 1st January 2012 and the 1st January 2015. Most indications for FE were determined by ­obstetricians, while some pregnant women were referred for FE by their rheumatologist, genetic medicine specialist or physicians of other subspecialties. A few pregnant women were examined at their own request. The incidence of CHD was 14.2% (196 fetuses were diagnosed out of 1380 examined), the most common being ventricular septal defect (25%), ­complex CHD (15.3%), arrhythmia (14.79%), cardiomyopathy (10.71%), coarctation of the aorta (7.65%), aortic valve stenosis (6.12%) and bicuspid aortic valve (3.06%). Pathology was more likely to be detected in pregnant women referred for FE with a specific indication, in comparison to those sent for a routine examination. Conclusion: Fetal echocardiography is diagnostically most efficient if we adhere to the prescribed indications which may indicate a primary heart disease (CHD in family, arrhythmias, CMP), fetal syndrome disease, diabetes mellitus or gestational diabetes, and systemic diseases of the mother’s linking tissue (positive specific antibodies)

Risk assessment for cancer development associated with the use of antihypertensives

Brojna su klinička istraživanja ispitivala mogući karcinogeni učinak anihipertenzivnih lijekova. Istraživan je njihov učinak na nastanak karcinoma prostate, kože, dojke, bubrega i pluća. Dokazano je da ukupni rizik od nastanka karcinoma pri uporabi svih antihipertenziva nije povišen. Za pojedine skupine karcinoma dokazano je smanjenje rizika od nastanka maligne bolesti uz uporabu antihipertenzivne terapije. Dobivene su vrijednosti jednake pri dugotrajnoj uporabi lijekova (> 7,5 godina); s duljinom primjene terapije ne dolazi do očekivanog porasta rizika, dok se u nekim istraživanjima vrijednost relativnog rizika s duljinom uporabe antihipertenziva smanjuje. Nijedna skupina antihipertenziva nije bila vezana s povišenim relativnim rizikom od nastanka karcinoma prostate, štoviše, uporaba beta-blokatora i dugogodišnja uporaba alfa-blokatora imala je protektivan učinak. Agencija za lijekove i medicinske proizvode i Europska agencija za lijekove obavještavaju o povišenom riziku od nastanka nemelanomskog raka kože uz uporabu hidroklorotiazida. Hrvatsko društvo za hipertenziju preporučuje razmotriti u kliničkoj praksi omjer koristi i rizika terapije hidroklorotiazidom, adekvatno informirati pacijenta te zajedno s njim donijeti odluku o daljnjoj uporabi hidroklorotiazida u terapiji. Relativni rizik za nastanak karcinoma dojke pri uporabi blokatora kalcijskih kanala, ali i drugih antihipertenziva nije bio povišen, vrijednosti su bile jednake onima u kontrolnim skupinama. Vjerojatnije je da je rizik od nastanka karcinoma bubrega vezan za samu patogenezu arterijske hipertenzije, a ne uz uporabu diuretske terapije. Zaključno, osim dokazane povezanosti uporabe hidroklorotiazida s nastankom nemelanomskog raka kože, valjanih dokaza za moguću karcinogenost drugih antihipertenziva još nema pa stoga preporučujemo u kliničkoj praksi nastaviti slijediti postojeće smjernice za liječenje arterijske hipertenzije uz reevaluaciju odluke o terapiji hidroklorotizadom u skladu s preporukama Hrvatskoga društva za hipertenziju.Numerous clinical trials have evaluated the potential cancerogenic effect of antihypertensive medications. Their influence on the development of prostate, skin, breast, kidney, and lung cancer has been examined. It was demonstrated that using antihypertensives does not elevate the total risk for cancer development. For some cancer groups there was even a reduction in risk of the development of malignant diseases under antihypertensive therapy. The results were the same in long-term use of the medications (>7.5 years), and longer application of the treatment did not lead to the expected increase in risk, with some studies finding a reduction in relative risk values with longer use of antihypertensives. No group of antihypertensives was associated with increased relative risk for the development of prostate cancer, and the use of beta-blockers and long-term use of alfa-blockers even had a protective effect. HALMED and the European Medicines Agency reported increased risk for the development of non-melanoma skin cancer with the use of hydrochlorothiazide. The Croatian Society of Hypertension recommends evaluating of the risk-benefit ratio of hydrochlorothiazide therapy in clinical practice, adequately informing the patient, and then deciding on the further use of hydrochlorothiazide in therapy together with the patient. The relative risk of breast cancer development was not increased due to the use of calcium channel blockers or other hypertensives, and the values did not differ from the control groups. It is more likely that the risk of kidney cancer development is associated with the pathogenesis of arterial hypertension rather than the use of diuretic therapy. In conclusion, apart from the demonstrated association between the use of hydrochlorothiazide and the development of non-melanoma skin cancer, there is still no valid evidence for the possible cancerogenic effect of other antihypertensives; in clinical practice we therefore recommend continuing to follow current guidelines for the treatment of arterial hypertension with a reevaluation of the use of hydrochlorothiazide therapy as recommended by the Croatian Society of Hypertension

Exercise heart rate recovery in obesity

Introduction: Obesity is an epidemic that carries significant cardiovascular (CV) burden. Autonomic dysfunction, characterized by reduced vagal tone and sympathetic overactivity, has been found in diabetes, hypertension, heart failure, metabolic syndrome, and other conditions. Heart rate decrease after exercise, or heart rate recovery (HRR) reflects cardiac autonomic activity. Decreased HRR is a powerful predictor of CV disease, CV and all-cause mortality.1-3 Patients and Methods: A total of 54 obese patients (24% male, 76% female), age 22-66 (mean 47 year), BMI 29.4-53.3 (mean 40.3 kg/m2), were enrolled in a multidisciplinary weight management program. Treadmill testing was done initially and after 6-month follow-up. Standard Bruce protocol was used to assess exercise capacity and passive HRR (15 sec, 3 and 6 min into the recovery period, as per institutional protocol). Control group was composed of age- and sex-matched non-obese subjects. Results: Obese subjects had significantly slower HRR (HRR0:15 6.1 vs. 9.1 BPM, HRR3:00 57.8 vs. 66.6 BPM, HRR6:00 63.3 vs. 72.7 BPM; p=0.0216, 0.0006, 0.0004, respectively). Exercise capacity was also significantly lower in comparison to control (6.7 vs. 8.6 METs; p=0.000001), with reduced exercise time (6.0 vs. 8.2 min; p=0.000001). Sixteen subjects that reached 6-month follow-up lost 5.4 kg on average. Exercise capacity increased mildly (6.4 to 7.1 METs; NS), as well as total exercise time (5.6 to 6.6 min; NS). Discussion and Conclusion: Physiological HRR kinetics follows exponential decay function. Rapid first phase, mediated by vagal reactivation is followed by a gradual HRR decline, dominated by sympathetic withdrawal. We found significantly slower HRR over different time-points in the obese, which reflects autonomic imbalance. Functional aerobic capacity was also significantly reduced. Somewhat improved functional capacity and dynamics of HRR after weight loss did not reach statistical power. To conclude, we found evidence of significantly impaired cardiac autonomic function in obese subjects, together with reduced functional capacity. As the study is ongoing, we hope to demonstrate sustained effect of exercise and diet on autonomic function. Potential benefit on mortality and CV risk reduction should encourage patients and health care providers to manage obesity more vigorously

Total atrioventricular block in Lyme borreliosis

Introduction: Lyme disease is caused by the spirochete Borrelia Brugdorferi. It manifests as erythema migrans but can also cause central neuropathy, arthritis and carditis.1 Cardiac manifestations include conduction abnormalities with varying degrees of atrioventricular block and other rhythm disturbances. 2 The incidence of Lyme disease increases from west to east across Europe, with the highest incidence in Slovenia (155/100 000).3 Case report: We observed a 32-year-old male patient who presented to the Emergency Department with recurrent syncope. Electrocardiography recorded intermittent total atrioventricular block, with an average heart rate of 25/min. A temporary pacemaker (Oscor Pace 101H, Single Chamber External Pacemaker) was implanted emergently using right jugular access. He had been on Sovsko lake near Čaglin village in Požega-Slavonia county 7 days prior to admittance, after which he had fever and chills for 2 days followed by diarrhea for 1 day. We started empirical treatment with intravenous ceftriaxone due to suspected Lyme disease. No tick bites on skin were found. Results: Results of serological testing showed that IgM Lyme titer (ELISA) was positive >5.23, also CLIA IgM were positive (IgM >190, IgG >240), followed by positive IgM and IgG Western Blot. Considering these results, we continued ceftriaxone treatment according to guidelines for 6 weeks. Echocardiography demonstrated normal left and right ventricular systolic function with no valvular dysfunction. First 3 days continuous pacing was required, afterwards for 7 days only intermittent pacing in night hours was required. In the end, the patient maintained normal sinus rhythm at 65-75 bpm. Two days after, the external pacemaker and active fixation lead was removed. Conclusion: Lyme borreliosis infection can cause conduction abnormalities, including total atrioventricular block in structurally healthy heart. Conduction abnormalities are reversible with the use of proper antibiotic treatment