Hearts, Volume 2, Issue 2 (June 2021) – 9 articles

A 66-year-old woman received a pacemaker implantation because of syncope with documented sinus arrest and junctional bradycardia. Three weeks later the pacemaker analysis revealed episodes of nonsustained ventricular tachycardia. Coronary angiography and invasive coronary assessment showed diffuse moderate stenosis but no significant ischemia. Three months later she experienced a new syncope and the pacemaker analysis showed runs of nonsustained ventricular tachycardia at the time of syncope. The combination of brady- and tachyarrhythmias raised concern for cardiac sarcoidosis. ¹⁸F-fluorodeoxyglucose positron emission tomography (PET) scan showed increased FDG uptake in the basal segments compatible with inflammatory disease. Cardiac magnetic resonance imaging showed late gadolinium enhancement in the same region of the PET-avid lesions. Diagnostic electrophysiologic study could induce VT. The diagnosis of cardiac sarcoidosis was made, for which high dose corticosteroids were prescribed and an upgrade to a dual chamber implantable cardioverter defibrillator was performed. Because of the localization of the lesions, an endomyocardial biopsy was not performed. All the lesions regressed completely on PET-scan after treatment with high dose corticosteroids. Full article

Background. Despite current trends toward early primary repair, the surgical systemic-to-pulmonary shunt is still considered the first-choice palliation in patients with critical tetralogy of Fallot (TOF) and duct-dependent pulmonary circulation unsuitable for primary repair. However, stenting of the right ventricular outflow tract (RVOT) is nowadays emerging as an effective alternative to surgical palliation in selected patients. Methods and results. RVOT stenting is usually performed from a venous route, either femoral or, in selected cases, the right internal jugular vein. Less frequently, mostly in pulmonary infundibular/valvar atresia, this procedure can be performed using a hybrid surgical/interventional approach by surgical exposure of the RVOT, puncture of the atretic valve, and stent deployment under direct vision. The size and type of the most appropriate stent may be chosen, based on ultrasound measurements of the RVOT, to cover the right ventricular infundibulum completely and, at the same time, sparing the pulmonary valve, unless significant pulmonary valve annulus hypoplasia and/or supra-valvular stenosis is a significant component of the obstruction. In the large series so far published, early mortality of RVOT stenting is less than 2%, comparing favourably with either Blalock-Thomas-Taussig shunt or early primary repair. In addition, morbidity and clinical sequelae of this approach do not significantly differ from surgical palliation, even if RVOT stenting shows lesser durability and a higher rate of trans-catheter re-interventions over a mid-term follow-up. Finally, similar but more balanced pulmonary artery growth than surgical palliation following RVOT stenting is reported over a mid-term follow-up. Conclusions. RVOT stenting is a technically feasible, well-tolerated, and effective palliation in critical TOF. This approach is cost-effective with respect to surgical palliation either in high-risk neonates or whenever a short-term pulmonary blood flow source is anticipated due to the early surgical repair. It effectively increases pulmonary blood flow, improves arterial saturation, and promotes balanced pulmonary artery growth over a mid-term follow-up. Full article

Physical exercise increases the relative risk of sudden cardiac death (SCD) in athletes when compared to a non-sporting population. Pre-participation evaluation (PPE) of athletes is thus of major importance. For Pacific Island athletes, medical guidelines recommend an echocardiography to complement a PPE including personal and family history, a physical examination and a resting twelve-lead electrocardiogram (ECG). Indeed, silent rheumatoid heart diseases found in up to 7.6% of adolescents give rise to severe valve lesions, which are the main causes of SCD in Pacific Island athletes. This short review examines the incidence rate of SCD in Pacific Island athletes and indicates how a questionnaire, physical examination, ECG and echocardiography can prevent it. Full article

Atrial fibrillation (AF) is the most common cardiac arrhythmia in the human population, with an estimated incidence of 1–2% in young adults but increasing to more than 10% in 80+ years patients. Pituitary Homeobox 2, Paired Like Homeodomain 2 (PITX2c) loss-of-function in mice revealed that this homeodomain (HD)-containing transcription factor plays a pivotal role in atrial electrophysiology and calcium homeostasis and point to PITX2 as a candidate gene for AF. To address this issue, we recruited 31 AF patients for genetic analyses of both the known risk alleles and PITX2c open reading frame (ORF) re-sequencing. We found two-point mutations in the homedomain of PITX2 and three other variants in the 5’untranslated region. A 65 years old male patient without 4q25 risk variants but with recurrent AF displayed two distinct HD-mutations, NM_000325.5:c.309G>C (Gln103His) and NM_000325.5:c.370G>A (Glu124Lys), which both resulted in a change within a highly conserved amino acid position. To address the functional impact of the PITX2 HD mutations, we generated plasmid constructs with mutated version of each nucleotide variant (MD4 and MD5, respectively) as well as a dominant negative control construct in which the PITX2 HD was lacking (DN). Functional analyses demonstrated PITX2c MD4 and PITX2c MD5 decreased Nppa-luciferase transactivation by 50% and 40%, respectively, similar to the PITX2c DN (50%), while Shox2 promoter repression was also impaired. Co-transactivation with other cardiac-enriched co-factors, such as Gata4 and Nkx2.5, was similarly impaired, further supporting the pivotal role of these mutations for correct PITX2c function. Furthermore, when expressed in HL1 cardiomyocyte cultures, the PITX2 mutants impaired endogenous expression of calcium regulatory proteins and induced alterations in sarcoplasmic reticulum (SR) calcium accumulation. This favored alternating and irregular calcium transient amplitudes, causing deterioration of the beat-to-beat stability upon elevation of the stimulation frequency. Overall this data demonstrate that these novel PITX2c HD-mutations might be causative of atrial fibrillation in the carrier. Full article

Sarcoidosis is a chronic multi-system disorder with an unknown etiology that can affect the cardiac tissue, resulting in Cardiac Sarcoidosis (CS). The majority of these CS cases are clinically silent, and when there are symptoms, the symptoms are vague and can have a lot in common with other common cardiac diseases. These symptoms can range from arrhythmias to heart failure. If CS goes undetected, it can lead to detrimental outcomes for patients. Diagnosis depends on timely utilization of imaging modalities and non-invasive testing, while in some cases, it does necessitate biopsy. Early diagnosis and treatment with immunosuppressive agents are crucial, and it is essential that follow-up testing be performed to ensure resolution and remission. This manuscript provides an in-depth review of CS and the current literature regarding CS diagnosis and treatment. Full article

The current treatment practice for Tetralogy of Fallot (TOF) is to undertake complete surgical repair between 6–9 months of age with excellent immediate and long-term results. In patients with increased cyanosis or frequent cyanotic spells, younger age of complete repair as early as 3 months is usually acceptable. Although neonatal TOF repair is reported with good immediate survival from a few centres, post-operative morbidity is significant, and the hospital stay is prolonged. Hence, in neonates and small term and preterm infants with severe cyanosis, palliative procedures such as modified Blalock-Taussig (BT) shunt, ductal stenting, right ventricular outflow tract (RVOT) stenting and balloon pulmonary valvotomy (BPV) have been reported. With the development of low-profile stents, an increasing clinician experience and more predictable outcome with both duct and RVOT stenting, these procedures have gained popularity as the preferred palliations for TOF at most centres. We reviewed the literature to analyse whether BPV for TOF palliation, a technique first reported three decades ago, still has a role in the present era of paediatric cardiac care. In this review, we have concluded that BPV has very specific indications in patients with TOF, with predominantly valvar pulmonary stenosis, and may be a preferred option over other palliative strategies in hypoxemic preterm or low-birth weight infants. Full article

Background and Aims: We hypothesized that maintaining a patient on moderate–high doses of potent inhalational agent for greater than 30 min during the post-bypass period would be an independent predictor of initiation and usage of either inotropic and/or vasopressor infusions. Setting and Design: This study is a retrospective design and approved by the institutional review board. The setting was a single-center, academic tertiary care hospital in Detroit, Michigan. Materials and Methods: Three-hundred, ninety-seven elective cardiac surgery patients were identified for chart review. Electronic medical records were reviewed to collect demographics and perioperative data. Statistics used include a propensity score regression adjusted analysis utilizing logistic regression models and a multivariable model. Results: A propensity score regression adjusted analysis was performed and then applied in both univariate and multivariate logistic regression models with a p value of <0.05 reaching statistical significance. Fifty-six percent of the participants had an exposure of greater than 30 min of a minimum alveolar concentration of isoflurane greater than 0.5 (ET_ISO ≥ 0.5_MAC, 30 _min) in the post-bypass period. After adjusting for propensity score, this was found to be a significant predictor of inotrope and/or vasoconstrictor use post-bypass (OR 2.49, 95% CI 1.15–5.38, p = 0.021). In the multivariate model, pulmonary hypertension (OR 5.9; 95% CI 1.33–26.28; p = 0.02), Euroscore II (2.73; 95% CI 1.35–5.5; p = 0.005), and cardiopulmonary bypass hours (OR 1.86; 95% CI 1.02–3.4; p = 0.042) emerged as significant. Conclusions: This study showed that an ET_ISO ≥ 0.5_MAC, 30 _min exposure during the immediate post-bypass period during elective cardiac surgery was an independent predictor of a patient being started on inotrope or vasoconstrictor infusions. Further research should consider a prospective design and examine depth of anesthesia during the post-bypass period. Full article

In recent decades there has been a relevant increase in the implantation rate of cardiac implantable electronic devices (CIEDs), albeit with relevant geographical inhomogeneities. Despite the positive impact on clinical outcomes, the possibility of major complications is not negligible, particularly with respect to CIED infections. CIED infections significantly affect morbidity and mortality, especially in instances of delayed diagnosis and appropriate treatment. In the present review, we will start to depict the factors underlying the development of CIED infection as well as the difficulties related to its diagnosis and treatment. We will explain the reasons underlying the need to focus on prophylaxis rather than treatment, in view of the poor outcomes despite improvements in lead extraction procedures. This will lead to the consideration of management of this complication in a hub-spoke manner, and to our analysis of the several technological and procedural improvements developed to minimize this complication. These include prolongation of CIED longevity, the development of leadless devices, and integrated prophylactic approaches. We will conclude with a discussion regarding new devices and strategies under development. This complete excursus will provide the reader with a new perspective on how a major complication can drive technological improvements. Full article

The ductal stenting (DS) is currently an acceptable palliative treatment in newborns suffering with duct-dependent pulmonary circulation. However, this procedure remains technically a challenge in complex ductal morphology, which may eventually lead to detrimental outcomes. This review is mainly focused on pre-procedural planning, essential instruments and practical approaches for DS, and post-procedural care. Full article