Background/Objectives: Heart rate variability (HRV) is a non-invasive marker of autonomic nervous system function with established prognostic value after acute coronary syndrome (ACS). The clinical relevance of temporal changes in short-term HRV remains insufficiently defined. This study evaluated short-term HRV dynamics and their association with mortality after ACS. Methods: This retrospective–prospective study included 230 patients with acute myocardial infarction. Five-minute resting ECG recordings were obtained on day 1 and day 21. Time- and frequency-domain HRV parameters were analyzed, and delta values were calculated. The primary endpoint was overall mortality. Survival was assessed using Kaplan–Meier analysis and Cox regression. Results: Patients who died during follow-up had lower HRV values on day 21 and more pronounced declines in selected parameters. In multivariable analysis, decreased ΔLF and shorter RR intervals independently predicted overall mortality. Conclusions: Short-term HRV provides a practical bedside assessment of autonomic function after ACS. Unfavorable temporal changes likely reflect persistent autonomic imbalance and may offer additional prognostic insight. Larger contemporary studies are needed to confirm these findings.

Background/Objectives: Aortic stenosis is associated with autonomic nervous system (ANS) imbalance, while diabetes mellitus is a major contributor to cardiac autonomic neuropathy. Their coexistence may result in more pronounced autonomic dysfunction not fully captured by conventional assessment. This study aimed to compare ANS function in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement (TAVR), according to diabetes status. Methods: This cross-sectional study included 74 patients with severe aortic stenosis referred for TAVR, including 21 patients with diabetes mellitus. Autonomic function was evaluated using non-invasive ECG-based analysis, incorporating short-term and 24 h Holter-derived heart rate variability (HRV), nonlinear Poincaré plot indices, and deceleration and acceleration capacity. Ambulatory blood pressure monitoring and standard clinical and echocardiographic assessment were performed. Results: Patients with diabetes mellitus demonstrated significantly lower long-term HRV parameters and reduced nonlinear Poincaré plot indices compared with non-diabetic patients, indicating altered autonomic modulation. Short-term HRV showed similar trends without statistical significance. Echocardiographic severity of aortic stenosis and left ventricular systolic function were comparable between groups. Conclusions: Autonomic dysfunction appears to be more pronounced in patients with severe aortic stenosis and diabetes mellitus, predominantly affecting parasympathetic modulation. ECG-derived autonomic parameters may offer complementary insight into ANS involvement in this population and warrant further investigation.

OBJECTIVES Aortic stenosis (AS) is the most common valvular heart disease, with transcatheter aortic valve implantation (TAVI) now preferred for select severe cases. This study evaluated the early safety and performance of the new Myval Octacor Transcatheter Heart Valve (THV) (Meril Life Sciences), for which limited clinical data exist. METHODS The authors retrospectively analyzed 43 consecutive patients with severe AS who underwent TAVI using the Myval Octacor THV at a tertiary cardiac center. Primary outcomes included all-cause mortality, stroke, major vascular complications, conduction abnormalities, new pacemaker implantation, paravalvular leak, and valve failure at 30 days follow-up. RESULTS The median age was 81 years (IQR: 7), and 22 patients (51.2%) were female. Coronary artery disease was present in 24 (55.8%). Technical success rate was 100%. Mean pressure gradient decreased significantly post-procedure (55 mm Hg [IQR: 24] vs 5 mm Hg [IQR: 2]; P ≤ .001). No in-hospital deaths occurred. Two patients (4.7%) received permanent pacemakers during hospitalization, and 3 (7.0%) required pacemakers within a week because of conduction issues. Two patients (4.7%) experienced Bleeding Academic Research Consortium Type 3a bleeding. At 30 days, 42 patients remained in follow-up (98%), with 55% improved to New York Heart Association Class I. No vascular complications, stroke, acute kidney injury, valve thrombosis, or endocarditis occurred. One patient had valve failure from a significant paravalvular leak and 1 noncardiac death occurred 2 weeks post-discharge. CONCLUSIONS Early outcomes suggest that the Myval Octacor THV is a safe and effective option for TAVI in severe AS; however, larger studies with longer follow-up are required.

Background/Objectives. Ebstein's anomaly (EA), which accounts for fewer than 1% of congenital heart diseases, and atrioventricular canal defect (AVCD), present in approximately 4-5% of cases, exceptionally coexist, with this combination observed in fewer than 0.5% of patients with AVCD. We aim to report the oldest documented case of a 45-year-old female with the exceptionally rare combination of complete AVCD, EA, and right ventricular hypoplasia and to provide a concise review of these anomalies. Case presentation. Diagnosed in early childhood with a complete AVCD, pulmonary stenosis, and right ventricular (RV) hypoplasia, the patient underwent palliative surgical intervention with a modified Blalock-Taussig shunt at the age of 10 but did not receive subsequent regular follow-up. Over the ensuing 35 years, she remained largely untreated until presentation at 45 years of age with progressive exertional dyspnea, central cyanosis, and palpitations, corresponding to NYHA class III. Comprehensive multimodal imaging, including transthoracic echocardiography and cardiac magnetic resonance, revealed a complete AVCD with moderate-to-severe mitral regurgitation secondary to an anterior mitral leaflet cleft, severe tricuspid regurgitation, RV hypoplasia, and hallmark features of EA. Given the complex cardiac anatomy and the elevated surgical risk, the patient was considered inoperable, and a strategy of conservative management with multidisciplinary follow-up was implemented. Conclusions. This case highlights the exceptional longevity of a patient with the rare coexistence of complete AVCD, EA, and RV hypoplasia, surviving 45 years from diagnosis despite limited early intervention. It underscores the importance of lifelong follow-up in complex congenital heart disease and illustrates the role of multimodal imaging in assessing anatomy and guiding management when surgical options are high-risk or not feasible.

Background and Objectives: Diabetes mellitus (DM) is a major risk factor for cardiovascular diseases (CVD), including acute myocardial infarction (MI), and is frequently associated with cardiac autonomic neuropathy (CAN). Post-MI autonomic dysfunction contributes to adverse outcomes, but data on prognostic markers in diabetic patients remain limited. This study aimed to (1) compare autonomic nervous system (ANS) function between patients with MI and DM (MI/DM), MI without DM, and DM without MI; (2) assess differences in MI/DM patients based on survival status; and (3) identify prognostic factors for all-cause mortality in diabetic patients following MI. Materials and Methods: This retrospective–prospective study included 375 patients: 93 MI/DM, 229 MI, and 53 DM. MI patients were treated with fibrinolytic or conservative therapy. All participants underwent cardiovascular reflex tests (CARTs) and 24 h Holter ECG with heart rate variability (HRV) analysis; DM patients without MI were tested in an outpatient setting. The primary endpoint was all-cause mortality during a median follow-up of 38 months. Univariable and multivariable Cox regression analyses were performed to determine mortality predictors. Results: Autonomic dysfunction was prevalent in all groups, with MI/DM patients showing the most pronounced impairment, particularly in parasympathetic function. MI/DM patients had significantly lower SDNN values and higher prevalence of definite parasympathetic dysfunction than other groups. In the MI/DM group, abnormal Valsalva maneuver (VM) was more frequent among non-survivors. Multivariable analysis identified abnormal VM and NSTEMI as predictors of overall mortality. Conclusions: Diabetic patients after MI exhibit the most severe autonomic impairment, predominantly parasympathetic, which may contribute to their increased cardiovascular risk. In this high-risk group, abnormal VM and NSTEMI presentations independently predict long-term mortality. Assessment of autonomic function, particularly VM, may provide valuable prognostic information and aid in risk stratification.

Background: Coxiella burnetii is a common zoonotic pathogen that can lead not only to acute or chronic Q fever but also to post-infectious syndromes, where autonomic nervous system (ANS) dysfunction has been suggested as a contributing mechanism. This study aimed to assess autonomic function in patients presenting with polymorphic symptoms, dysautonomia, or ME/CFS who had serological evidence of acute infection with Coxiella burnetii. Methods: A total of 156 participants were evaluated, including 100 seropositive patients and 56 matched controls. All subjects underwent standardized cardiovascular reflex tests (CART), beat-to-beat analysis of heart rate and blood pressure with baroreflex indices, 24 h Holter ECG with HRV assessment, and, in the Coxiella group, head-up tilt testing (HUTT). Results: A significantly higher prevalence of autonomic dysfunction was observed in the Coxiella group, predominantly affecting parasympathetic regulation, with abnormal CART scores, reduced LF power and baroreflex effectiveness, and a high rate of positive HUTT findings characterized by extreme blood pressure variability. Although long-term HRV measures did not differ significantly between groups, short-term indices consistently indicated ANS impairment. Conclusions: These findings suggest that Coxiella burnetii infection may trigger persistent autonomic dysfunction, potentially contributing to the development of ME/CFS and syncope in affected individuals. Further longitudinal studies are needed to clarify pathophysiological mechanisms and clinical implications.

Background: Refractory atrioventricular nodal reentrant tachycardia (AVNRT) is a rare condition, but poses a clinical challenge after failed standard ablation. Very high-power, short-duration (vHPSD) radiofrequency (RF) ablation has not yet been explored in slow pathway ablation/modification. Case Summary: A 61-year-old woman with recurrent AVNRT despite two prior ablations and multiple antiarrhythmics underwent successful slow pathway ablation using a 90-watt, 4-s vHPSD protocol. CARTO-guided mapping localized the presumed slow pathway, followed by several 90 W applications. Transient second-degree AV block (Wenckebach type) occurred and resolved spontaneously. The patient remained arrhythmia-free at 6-month follow-up. Conclusions: This is the first reported clinical use of 90 W/4 s RF energy for AVNRT. The vHPSD approach may offer an effective alternative for patients with refractory AVNRT.

Background/Objectives: Postural orthostatic tachycardia syndrome (POTS) is a form of dysautonomia characterized by excessive tachycardia during orthostatic stress. It is frequently observed in patients with syncope, Chronic Fatigue Syndrome (CFS), and post-COVID-19 syndrome (PCS), yet the underlying mechanisms may differ across these conditions. This study aimed to assess autonomic nervous system (ANS) function in patients with syncope, CFS of insidious onset, and CFS post-COVID-19 who presented with POTS, and to compare them with age- and sex-matched patients without POTS. Methods: In this retrospective cross-sectional study, 138 patients over 18 years of age were included following head-up tilt testing (HUTT). Patients were divided into six groups: syncope with and without POTS, CFS with insidious onset with and without POTS, and CFS post-COVID-19 with and without POTS. All participants underwent HUTT, cardiovascular reflex testing (CART) by Ewing, five-minute resting ECG with short-term Heart Rate Variability (HRV) analysis, and 24 h Holter ECG monitoring. Results: The prevalence of POTS across groups ranged from 5% to 7%. Female predominance was consistent across all subgroups. In syncope with POTS, hypertensive responses during HUTT, lower rates of normal Valsalva maneuver results, and reduced HF values in short-term HRV suggested baroreceptor dysfunction with sympathetic overdrive. In both CFS subgroups with POTS, CART revealed higher rates of definite parasympathetic dysfunction, along with more frequent extreme blood pressure variation during HUTT and reduced vagally mediated HRV parameters (rMSSD, pNN50). Across groups, no significant differences were observed with regard to long-term HRV across groups. Conclusions: Distinct autonomic profiles were identified in POTS patients depending on the underlying condition. Syncope-related POTS was associated with baroreceptor dysfunction and sympathetic predominance, whereas CFS-related POTS was characterized by parasympathetic impairment and impaired short-term baroreflex regulation. Evaluating dysautonomia patterns across disease contexts may inform tailored therapeutic strategies and improve management of patients with POTS.

Background and Clinical Significance: Concomitant severe aortic stenosis (AS) and abdominal aortic aneurysm (AAA) in elderly patients presents a significant therapeutic challenge. While transcatheter aortic valve replacement (TAVR) and endovascular aneurysm repair (EVAR) have become established minimally invasive treatments for high-risk patients, simultaneous management of both conditions remains rare. Case Presentation: We report the first documented case in Serbia of a simultaneous TAVR and EVAR in a 75-year-old male with severe symptomatic AS and AAA. The patient had a history of hypertension, diabetes mellitus, atrial fibrillation, prior radiofrequency pulmonary vein ablation, and pacemaker implantation. Echocardiography demonstrated severe AS with a transvalvular gradient of 116/61 mmHg, an aortic valve area of 0.6 cm2, and a left ventricular ejection fraction of 30–35%. Coronary angiography revealed 50–60% stenosis of the right coronary artery. Following evaluation by a multidisciplinary Heart and Vascular Team, a combined procedure was performed under general anesthesia via bilateral femoral access. TAVR with a Medtronic Evolut R valve was successfully deployed, followed by EVAR with satisfactory stent graft positioning and angiographic results. The patient’s postoperative course was uneventful, and he was discharged on the ninth day. At six-month follow-up, echocardiography showed optimal valve function, and CT identified a type II endoleak, which was managed conservatively. Conclusions: This case demonstrates the feasibility and safety of simultaneous TAVR and EVAR in a high-risk elderly patient, emphasizing the importance of careful preoperative planning and a coordinated multidisciplinary approach. Further studies are warranted to establish standardized guidelines for the management of patients with coexisting severe AS and AAA.

Autonomic nervous system (ANS) dysfunction has emerged as a central feature of post-infectious syndromes, including post-COVID syndrome (PCS), chronic fatigue syndrome (CFS), and late-stage Lyme disease. This cross-sectional study included 1036 patients evaluated in the Neurocardiological Laboratory of the Institute for Cardiovascular Diseases “Dedinje,” divided into four groups: PCS, CFS after COVID-19, CFS of insidious onset, and Lyme disease. All patients underwent head-up tilt testing (HUTT), and serological testing was performed in accredited institutions. The Lyme disease group demonstrated the highest prevalence of positive HUTT responses and a significantly greater frequency of orthostatic hypotension and syncope. Approximately 50–65% of patients in the PCS and Lyme groups were positive for IgM antibodies against at least one microorganism, with more than 10% showing positivity for three or more pathogens. Logistic regression analysis revealed that, beyond classical hemodynamic parameters, antibody status served as a significant predictor of HUTT outcomes, with specific associations identified for HSV-1, HHV-6, Coxiella burnetii, Toxoplasma gondii, and Borrelia spp. Multinomial regression further indicated that negative IgG antibodies, particularly to HSV-1 and VZV, predicted Lyme disease group membership. These findings support the hypothesis that ANS dysfunction in post-infectious syndromes may be driven by persistent or prior infections, highlighting the need for integrative diagnostic approaches.