The Journal of Tehran University Heart Center
Volume:18 Issue: 2, Apr 2023

Cardiac surgery rapidly gained much publicity following its establishment in the late 50s. Nonetheless, subsequent advances in percutaneous techniques in the domain of cardiovascular diseases overshadowed cardiac surgery for a substantial period until a recent project rekindled interest, among scientists and patients, in cardiac surgery. The project in question was the xenotransplantation of a pig heart to a human, performed on January 7th, 2022. The patient survived for approximately 2 months with satisfactory hemodynamics and without mechanical and pharmaceutical support. The cause of his death has yet to be fully elucidated, although a pig virus seems to be the likely culprit. While it was the first transplantation of a pig heart to a human, by no means was it the first heart xenotransplantation. Indeed, the first transplantation ever was the xenotransplantation of a chimpanzee heart to a human performed by Hardy1 in 1964. The outcome was, however, disappointing, with Hardy facing many problems in the following years due to his perceived “unethical” procedure. He was even expelled from the American Medical Association for a while. All this led to the abandonment of such techniques for about 50 years, although the science has evolved greatly since then, with parts of animals such as swine pericardium being widely used in common practice. The recent project was pioneered by Griffith on the strength of advances in immunosuppression. For instance, xenotransplantation from a pig heart to a non-human heart was investigated, and the results showed that cardiac xenotransplantation was feasible in the midterm.2 A landmark in this field was the publication of a study in 2018 in which modified pig hearts were transplanted in chimpanzees, and the survival exceeded 195 days in 4 out of 5 recipients.3 The results of that study raised the interest in heart xenotransplantation among scientists. Pierson4 claimed that such results, on condition of reproducibility, could pave the way toward further clinical heart xenotransplantation trials. Still, Reichart5 opined that a more acceptable costimulation blockade was required for future human applications and safe donor animals that would not cause harmful infectious diseases in human recipients. From a technical perspective, pig heart donor grafts offer such advantages as similarity with the human heart, relatively

 Cardiovascular diseases, specifically acute myocardial infarction (AMI), are the leading cause of death worldwide. In this review, we explain the characteristics of AMI in Iran.

 We searched PubMed, Google, and Google Scholar for articles containing myocardial infarction, STEMI, and MI+ Iran in English and Persian words.

 The age-standardized incidence rate of MI was 73.3 per 100 000. The mean±SD age of patients was 61.20±13.40 years. In-hospital mortality of patients with AMI in the IMIR was 12.1%. Concerning AMI complications reported in the IMIR, 5.8% of patients experienced ventricular tachycardia, and 2.5% experienced ventricular fibrillation. The 1-year mortality rate in the IPACE2 study was 4.3%.

 Only a few national studies are available in Iran regarding patients with AMI. A federal surveillance program continuously monitoring and tracking coronary events is essential to improve the general population’s health.

The systemic immune-inflammation index (SII) has recently been investigated for cardiovascular diseases. We aimed to evaluate the relationship between SII and left atrial thrombosis (LAT).

This retrospective, case-control study recruited patients with nonvalvular atrial fibrillation (NVAF) who underwent transesophageal echocardiography (TEE) for LAT detection before cardioversion or catheter ablation at a tertiary hospital between 2012 and 2021. Demographic characteristics were obtained from the hospital data system. According to TEE findings, the patients were categorized into LAT (+) and (-) groups. Age, gender, history of chronic diseases, urea, creatinine, albumin, hemogram parameters, the neutrophil-lymphocyte ratio (NLR), the platelet-lymphocyte ratio (PLR), SII, the CHADS₂ score, the CHA₂DS₂-VASc score, echocardiographic parameters, antiaggregant-anticoagulant use, and nonparoxysmal atrial fibrillation were included and analyzed.

The study population consisted of 403 patients, including 228 men (56.6%), at a mean age of 60.84±12.26 years. A high white blood cell count (WBC) (OR, 1.26; 95% CI, 1.05 to 1.51; P=0.013), a high SII (OR, 1.00, 95% CI, 1.00 to 1.00; P=0.003), and a low ejection fraction (OR, 0.95; 95% CI, 0.90 to 0.99; P=0.018) were independent predictors of LAT (+). A spontaneous echo contrast (OR, 2.43; 95% CI, 1.35 to 4.39; P=0.003) was associated with LAT (+). SII values above 693.6 predicted LAT (+) with 71.6% sensitivity and 71.7% specificity (AUC, 0.77; P<0.001). The predictiveness of SII was similar to that of NLR (0.77 vs 0.74, P=0.093) but higher than PLR (0.77 vs 0.67; P<0.001) and WBC (0.77 vs 0.69; P=0.031).

SII is an independent predictor of LAT in patients with NVAF.

The present study aimed to determine the cost-effectiveness of ticagrelor compared with clopidogrel in Iranian patients with acute coronary syndrome (ACS).

A 1-year decision tree model combined with a 20-year Markov transition model was used to simulate the longterm cost and effectiveness of both ticagrelor and clopidogrel in Iran based on an Iranian payer’s perspective. Clinical efficacy data were extracted from the PLATO trial and other published studies. Costs were estimated based on local prices in public sectors. Deterministic and probabilistic sensitivity analyses were used to test the robustness of base-case results over the uncertainties of model inputs. All calculations, analyses, and modeling were done in TreeAge 2011 and Microsoft Excel 2013.

Compared with clopidogrel, the treatment of Iranian ACS patients with ticagrelor for 20 years resulted in an additional cost of US$ 2.39 in a hypothetical cohort of 1000 patients. However, ticagrelor led to 7.2 quality-adjusted lifeyears (QALYs) gained per 1000 hypothetical patients. Accordingly, the estimated incremental cost-effectiveness ratio for this analysis was US$ 332.032 per 1 QALY gained.

Ticagrelor was a cost-effective antiplatelet medicine compared with clopidogrel in Iranian patients with ACS. This could help Iran’s policymakers to allocate resources more efficiently to ACS.

A comprehensive strategy to reduce the complications of hypertension (HTN) should include prevention approaches, such as increasing awareness, early diagnosis, and adequate treatment. The present study aimed to assess awareness, treatment, and control of HTN and their related factors in Kherameh, Iran.

This cross-sectional study was performed on 10 663 individuals aged between 40 and 70 years using the Kherameh cohort data. HTN was defined as either systolic/diastolic blood pressure ≥140/90 mmHg or taking medications. Logistic regression was used to investigate the relationship between awareness, treatment, and control of HTN and demographic factors, comorbidities, and a family history of diseases.

Out of 10 663 participants, 4719 (44.3%) were men, and the average age of the participants was 51.94±8.27 years. The rates of the prevalence, awareness, treatment, and control of HTN were 27.7% (95% CI, 26.86 to 28.54), 80.3% (95% CI, 79.56 to 81.04), 78% (95% CI, 77.22 to 78.78), and 53.6% (95% CI, 52.66 to 54.54), respectively. Age, gender, body mass index, and cardiovascular disease were associated with all the dependent variables in the regression model. Additionally, occupation, diabetes, chronic diseases, a history of cardiovascular disease in first and second-degree relatives and a history of chronic diseases in second-degree relatives were related to all the dependent variables except for treatment.

A high percentage of the patients were aware of their disease, but a smaller proportion were on medication. Consequently, about half the patients had blood pressure below 140/90 mmHg.

The use of cardiac resynchronization therapy (CRT) in heart failure patients with right bundle branch block (RBBB) is under debate. We present early and late echocardiographic characteristics of a series of heart failure patients with RBBB who underwent CRT.

In this retrospective descriptive study, 18 patients with RBBB in the surface electrocardiogram underwent CRT between 2005 and 2015. All the patients had the New York Heart Association functional class III/IV, a left ventricular ejection fraction (LVEF) ≤35%, and a QRS duration ≥120 milliseconds. The median follow-up duration was 19 months. The echocardiographic response was based on a ≥5% increase in LVEF.

Within 48 hours after CRT implantation, LVEF increased from 24.58%±7.08% before to 28.46±8.91% after CRT (P=0.005) and to 30.00±9.44% at follow-up (P=0.008). Among the 18 patients, 12 (66.7%) were responders within 48 hours after CRT. The following baseline echocardiographic parameters were higher in the responders than in those without an increased LVEF, although the difference did not reach statistical significance: septal-to-lateral wall delay (48.33±33.53 vs 43.33±38.82 ms), anteroseptal-to-posterior wall delay (41.7±1.75 vs 38.33±18.35 ms), and interventricular mechanical delay (48.50±21.13 vs 31.17±19.93 ms). The mean QRS duration was higher in the responders than in the non-responders (183.58±40.69 vs 169.00±27.36 ms). Death was reported in 3 out of the 18 patients (16.7%) at follow-up. The 3 deceased patients had a higher baseline interventricular mechanical delay than those who survived.

Our results indicated that patients with RBBB might benefit from CRT. Further, patients with higher intra and interventricular dyssynchrony and a wider QRS may show better responses.

Atrial fibrillation (AF) is a supraventricular tachyarrhythmia characterized by disorganized atrial activity and subsequent mechanical atrial failure. Postoperative AF is a frequent complication of coronary artery bypass grafting (CABG). Although there is evidence of decreased AF after CABG with statin usage, information is scarce regarding a direct comparison between atorvastatin and rosuvastatin. The present study was conducted to compare the efficacy of rosuvastatin and atorvastatin in preventing post-CABG AF.

The present double-blind randomized comparative clinical trial selected CABG candidates with stable ischemic heart disease or acute coronary syndromes. Atorvastatin (40 mg per day) or rosuvastatin (20 mg per day) was prescribed 1 week before surgery, and the outcomes were compared.

Two-hundred patients, 100 cases in each group, completed the study. Twenty-five patients in each group were female, and the mean age was 59.30±8.42 years in the rosuvastatin group and 60.13±9.40 years in the atorvastatin group (P=0.513). The frequency of AF was 31% in the atorvastatin group and 27% in the rosuvastatin group (P=0.534). No significant differences existed between the groups concerning the length of hospital and ICU stay (P=0.333 and P=0.161) and in-hospital and 3-month mortality (P=0.315 and P=0.648). A subgroup analysis of only patients with stable ischemic heart disease could not detect a significant difference between the study groups in any of the investigated outcomes. Our logistic regression analysis showed an association only between age and the incidence of AF after CABG (OR, 1.12; 95% CI, 1.05 to 1.20; P<0.01).

Rosuvastatin and atorvastatin are similar concerning the prevention of post-CABG AF, but there is a need for future well-designed multicenter studies on this topic.

Ventricular arrhythmias (VAs), which result from acute myocardial infarction and revascularization, are preventable causes of sudden cardiac death. This study aimed to determine the incidence, types, and risk factors of VAs in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention (PCI).

This cross-sectional study was conducted at the cardiology department of a tertiary care cardiac center in Zanjan, Iran. All the patients were monitored during hospitalization, and the incidence of cardiac arrhythmias and the outcomes were recorded.

Among 315 patients, the mean age was 62.14±10.11 years, and 76.2% were male. Male gender was significantly associated with VA occurrence (P=0.038). Among the patients, 50.5% had VAs, of which 26.4% were sustained ventricular tachycardia (sustained VT) and ventricular fibrillation (VF). Sustained VT and VF, but not total arrhythmias, were more common in anterior infarctions. Most arrhythmias occurred during the first 12 hours, and frequent premature ventricular contractions (43.3%) and idioventricular rhythm (20.1%) were the most common. A history of PCI and coronary artery bypass grafting (CABG) was associated with substantially reduced arrhythmias (P=0.017 and P=0.013, respectively). However, cardiovascular risk factors exerted no statistically significant effects on the VA type.

Approximately half of our patients experienced reperfusion-induced VAs. Overall, gender and a history of PCI and CABG were significantly associated with VA occurrence. Therefore, males and patients without a positive history of PCI and CABG should receive antiarrhythmic drugs as a precaution.

Myocardial perfusion imaging (MPI) is a noninvasive method with acceptable sensitivity and specificity in diagnosing coronary artery disease (CAD) in moderate-risk patients, including those with CAD risk factors.

The present cross-sectional, prospective study was conducted on 4886 patients from April 2020 through March 2023 at Chamran and Tehran Heart Center hospitals. A questionnaire regarding anthropometric variables, demographic characteristics, CAD risk factors, and MPI findings was designed.

Totally, 2179 patients (44.6%) had abnormal MPI. Patients with abnormal MPI were significantly older than those with normal MPI. Older age (OR, 1.64; 95% CI, 1.2 to 1.72; P<0.001), diabetes mellitus (DM) (OR, 1.36; 95% CI, 1.1 to 1.48; P=0.012), hypertension (OR, 1.24; 95% CI, 1.04 to 1.37; P=0.032), and dyslipidemia (OR, 1.54; 95% CI, 1.25 to 1.8; P<0.001) were associated with abnormal MPI independently. Patients with more CAD risk factors were more likely to have abnormal MPI. Thus, in patients without or at most with 1 risk factor and those with 8 CAD risk factors, the likelihood of abnormal MPI was 3.7% and 76.2%, respectively. The frequency of left ventricular dilation and right ventricular prominence was significantly higher in patients with older age (P<0.001 and P=0.043, respectively), dyslipidemia (P<0.001 and P=0.007, respectively), DM (P<0.001 and P<0.001, respectively), and hypertension (P=0.048 and P=0.057, respectively).

Individuals with CAD risk factors, especially those with older age, DM, hypertension, or dyslipidemia, require meticulous attention during CAD evaluation, particularly via MPI.

Studies have shown a decline in the admission rates of various diseases during the COVID-19 pandemic. Prosthetic valve thrombosis (PVT) is a rare condition followed by surgical or transcatheter valvular interventions. Considering the lack of data on hospitalization rates due to PVT during the pandemic, this study evaluated the implications of the COVID-19 pandemic on PVT admissions and characteristics in a tertiary referral center.

Data from all the consecutive patients hospitalized due to PVT between February 2020 and February 2021 (the first year of the pandemic) were collected from medical records and compared clinically with the corresponding time before the pandemic (February 2019 through February 2020). Variables of interest included the number of hospitalization, patient and valve characteristics, diagnostic and management strategies, and in-hospital events.

Forty patients (32.5% male, age: 54.0 [46.5-62.0 y] comprised the study population. We observed a considerable decline in hospitalization rates during the pandemic, from 31 to 9 patients. Admitted patients were 8 years younger, had a higher proportion of the New York Heart Association functional class III or IV symptoms (44.4% vs 22.6%), were more often treated with fibrinolysis (33.3% vs 22.6%) or surgical approaches (33.3% vs 22.6%), and were discharged 6 days sooner.

We described a reduction in PVT hospitalization. Patients presented with a higher proportion of severe dyspnea and had increased treatment with fibrinolysis/surgical approaches. These observations highlight the necessity of the active surveillance of patients with prosthetic valves by caregivers for timely diagnosis and appropriate management during the pandemic.

Coronary artery aneurysms (CAAs) occur when an artery dilates 1.5 times the reference vessel. They occur most commonly because of atherosclerosis. CAAs are a rare phenomenon, and it is even rarer to find a giant CAA, which is roughly defined as a size 400% above the reference vessel. Giant CAAs are commonly found in the right coronary artery. The sinoatrial nodal artery (SNA) is among the least common sites for CAA involvement. Sometimes, communication exists between the aneurysm and a chamber of the heart or a great vessel. The consequences of the fistula depend on its size. Because of the rarity of the condition, guidelines are not well developed. However, small CAAs can be managed conservatively, whereas giant CAAs require resection, ligation, and bypass grafting. CAAs have a predilection for males and the elderly. We describe a 40-yearold South Asian woman presenting with mild dyspnea on exertion of 1 year’s duration. Echocardiography showed a 60×60 mm cystic sac, subsequently confirmed by computerized tomography, which showed 3 large aneurysms (70×61 mm) and 3 small aneurysms in the SNA. Coronary angiography illustrated that the SNA branched off the left main coronary artery, and the aneurysm communicated with the right coronary artery. The aneurysm was partially resected and plicated.

Congenital coronary artery anomalies are relatively rare, occurring in approximately 0.6%-1.3% of cases undergoing coronary angiography. Among these anomalies, a unique cardiac abnormality known as a dual left anterior descending artery (LAD) stands out. A dual LAD is characterized by the presence of 2 LADs in the anterior interventricular sulcus. This structural deviation consists of a shorter LAD that terminates high in the anterior interventricular sulcus and a longer LAD that extends to the distal sulcus, supplying blood to the cardiac apex. Percutaneous procedures on dual LADs are even less frequent. We describe a 53-year-old woman with typical burning chest pain, ST-elevation in leads I and aVL, and positive troponin I enzyme. Coronary angiography revealed a thrombotic lesion with 99% stenosis at the proximal part of the LAD. The main LAD originated properly from the left coronary cusp, and the remainder of its course was supplied by a second branch originating from the right coronary cusp. Computed tomography angiography and echocardiography were performed for the LAD course. The patient was discharged after an uneventful 1-week hospital stay.

Our case is particularly noteworthy for several reasons. Firstly, this dual LAD anomaly is uncommon, and patients with dual LADs less frequently have a ramus artery. Secondly, there have been only a few documented cases of percutaneous transluminal coronary angioplasty performed on short LADs. The key takeaway from this scintillating case study is the significance of identifying the artery responsible for blood supply to the cardiac apex.