Aortic Coarctation

Follow-up outcomes and effectiveness of stent implantation for aortic coarctation: A systematic review and meta-analysis

BACKGROUND

The authors aim to investigate the clinical implications of stent use for the management of CoA.

METHODS

All observational studies on stent implantation for the treatment of aortic coarctation and the relevant RCTs were systematically retrieved. Outcomes included the immediate success rate, pre- and post-stent gradient, survival, minor and major complications, restenosis, post-stent systolic blood pressure, and reintervention rate. The analysis was further stratified by CoA type, stent type, and the mean age of the patients.

RESULTS

Our meta-analysis incorporated 66 eligible studies involving 3,880 patients. The success rates for stent placement, defined as achieving post-treatment gradients of ≤20 mmHg and 10 mmHg, 0.96 (95% CI: 0.95 - 0.97; I2 = 59.83%) and 0.92 (95% CI: 0.89 - 0.95, I2 = 77.63%) respectively. The complication rates were quite low, with minor and major complication rates of 0.017 (95% CI: 0.013 - 0.021) and 0.007 (95% CI: 0.005 - 0.009), respectively. Unplanned reinterventions were required at a rate of 0.021 (95% CI: 0.015 - 0.026). At a mean follow-up of 2.9 years, 97% of the patients survived and 28% remained on antihypertensive therapy. While immediate effectiveness was consistent across age groups, complications were more prevalent in patients aged <20 years, and long-term efficacy was lower in those aged >20 years. Encouragingly, in neonates and infants, CoA stenting yielded results comparable to those observed in older children.

CONCLUSION

These findings underscore the overall favorable outcomes of stent placement for aortic coarctation, with considerations for age-related variations in complications and long-term efficacy.

Critical left main coronary artery stenosis presenting as cardiac arrest in coarctation of the aorta patient

Congenital coronary artery stenosis coexisting with aortic coarctation in nonsyndromic patients has not previously been reported. This report describes a nonsyndromic aortic coarctation patient who experienced intraoperative cardiac arrest due to a previously undiagnosed critical left main coronary artery stenosis. The patient was successfully resuscitated, underwent patch coronary ostioplasty, and was discharged home. He remains well for four months following repair.

Evaluation of short and mid-term clinical outcomes in patients with aortic coarctation treated with self-expandable stents

The present study aimed to evaluate the outcomes of percutaneous treatment of aortic coarctation using self-expandable uncovered Nitinol stents. We conducted a retrospective clinical data review of all patients with aortic coarctation and treated with self-expandable uncovered Nitinol stents at our institution between 2009 and 2019. The gradient pressure across the coarctation site was measured using aortography. Follow-up echocardiography and computed tomography angiography were performed to assess possible stent complications. A total of 127 stents were successfully implanted in 125 patients (64.8% males) with a mean age of 35.36 ± 11.9 years. The gradient across the coarctation site decreased significantly from 67.48 ± 14.79 to 5.04 ± 3.01 mmHg (P < 0.001) after self-expandable stent implantation. Systolic blood pressure (SBP) decreased significantly from 175.53 ± 15.99 to 147.22 ± 12.83 mmHg (P < 0.001) after self-expandable stenting. There were no major technical or clinical complications, including balloon rupture, aneurysmal formation, infection, secondary stent migration, thrombosis, death during the procedure, and in-hospital mortality. On a mean follow-up of 48 ± 23.6 months (12-120 months), the gradient [from 59.43 ± 15.42 to 3.72 ± 1.38 mmHg (P < 0.001)] and SBP [from 175.53 ± 15.99 to 127.99 ± 7.82 mmHg (P < 0.001)] decreased significantly. There was no mortality, aneurysmal formation in the stent site, dislocation, or aortic re-stenosis requiring intervention during mid-term follow-up. Treatment of aortic coarctation using a self-expandable uncovered nitinol stent is safe and effective with promising mid-term outcomes.

Mechanical Thrombectomy via Transbrachial Approach in the Emergency Management of Acute Ischemic Stroke Patients with Aortic Pathologies: Our Experience and Literature Review

STUDY DESIGN

Mechanical thrombectomy (MT) via the transbrachial approach (TBA) is a very rare option used in cases of patients with aortic pathologies and acute ischemic stroke (AIS) due to the insufficient evidence in the literature, the difficulty from a technical point of view and the result of this technique influenced by the complications that frequently accompany it.

BACKGROUND

Only a few cases of patients with aortic pathologies and acute ischemic stroke where MT via TBA were reported in the literature, and its application in the emergency management of AIS has still not been dealt with in detail.

OBJECTIVES

Out of a need to clarify and clearly emphasize the effectiveness of this approach in emergency MT via TBA in patients with AIS and aortic pathologies, this literature review and case report has the following objectives: the first one is the presentation of an emergency MT via transbrachial approach performed in a 44-year-old patient with AIS and diagnosed aortic coarctation during transfemural approach (TFA), with successful reperfusion in our department and the second one is to review the cases reports of patients with different aortic pathologies and AIS reperfusion therapy performed by MT via TBA from the literature.

METHODS

A total of nine cases (one personal case and eight published cases) were revised in terms of aortic pathologies type, reperfusion therapy type, and the complication of both mechanical thrombectomy and local transbrachial approach.

RESULTS

Mechanical thrombectomy through the transbrachial approach was the first choice in more than half of these cases (55.55%, n = 5 cases) in the treatment of acute ischemic stroke in the presence of previously diagnosed aortic pathologies. In one-third of all cases (33.33%, n = 3, our case and 2 case reports from the literature), the transbrachial approach was chosen after attempting to advance the guiding catheter through the transfemoral approach and intraprocedural diagnosis of aortic pathology. In only one case, after an ultrasound evaluation of the radial artery that showed a monophasic flow, MT was performed via TBA. Local transbrachial complication was reported in one case, and in two other cases, it was not stated if there were such complications. Hemorrhagic transformation of AIS was reported in two cases that underwent MT-only cerebral reperfusion via TBA, one with acute aortic dissection type A and our case of previously undiagnosed aortic coarctation. In the cases in whom short and long-term follow-up was reported, the outcome of treatment, which was not exclusively endovascular (77.77% cases with only MT and 33.33% with association of first thrombolysis and after MT), was good (six from nine patients). In two case reports, the outcomes were not stated, and one patient died after a long hospitalization in the intensive care unit from respiratory complications (our patient).

CONCLUSIONS

Being a clinical emergency, acute ischemic stroke requires urgent medical intervention. In patients with aortic pathologies, where acute ischemic stroke emergency care is a challenge, mechanical thrombectomy via the transbrachial approach is a safe alternative method for cerebral reperfusion.

Role of Computed Tomography Angiography in the Short-Term Follow-up of Aortic Coarctation Repair

INTRODUCTION

Coarctation of the aorta (CoA) is a narrowing of the thoracic aorta that often manifests as discrete stenosis but may be tortuous or in long segment. The study aimed to evaluate pre and post-surgical aspects of pediatric patients submitted to CoA surgical correction and to identify possible predisposing factors for aortic recoarctation.

METHODS

Twenty-five patients were divided into groups according to presence (N=8) or absence (N=17) of recoarctation after surgical correction of CoA and evaluated according to clinical-demographic profile, vascular characteristics via computed angiotomography (CAT), and other pathological conditions.

RESULTS

Majority of males (64%), ≥ 15 days old (76%), ≥ 2.5 kg (80%). There was similarity between groups with and without recoarctation regarding sex (male: 87% vs. 53%; P=0.277), age (≥ 15 days: 62.5 vs. 82%; P=0.505), and weight (≥ 2.5 kg: 87.5 vs. 76.5; P=0,492). Altered values of aortic root/Valsalva diameter, proximal transverse arch, and distal isthmus, and normal values for aorta prevailed in preoperative CAT. Normal values for the aortic root/Valsalva sinus diameter were observed with and without recoarctation, the same for both groups regarding ascending and descending aorta in postoperative CAT. No significant difference for altered values of proximal transverse arch and alteration in distal isthmus was observed.

CONCLUSION

No predictive risk for recoarctation was observed. CTA proved to be important in CoA diagnosis and management, since CoA is mainly related with altered diameter of aortic root/sinus of Valsalva and proximal and distal aortic arch/isthmus, however, it failed to show predictive risk for recoarctation.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Coarctation of the Aorta: Modern Paradigms Across the Lifespan

While coarctation of the aorta varies greatly in both severity and age at presentation, all patients are at increased risk of hypertension both before and after repair. Despite advances in knowledge about genetic etiologies, pathophysiologic mechanisms, and optimal repair strategies, patients with repaired coarctation of the aorta remain at increased risk of acquired cardiovascular disease. The aims of this review are to describe the management of coarctation of the aorta at all ages before and after repair, highlight pathophysiologic mechanisms of hypertension, and review long-term follow-up considerations.

Coarctation Angioplasty in Young Children: Does IMPACT Registry Data Accurately Reflect Clinical Outcomes?

Balloon angioplasty for recoarctation of the aorta is routinely performed in young children and is considered successful when the systolic gradient is reduced to < 10 mmHg. IMPACT defines acute procedural success solely based on a final gradient of < 10 mmHg and stratifies participating institutions based on these acute outcomes. Between February 2012 and December 2020, IMPACT data was analyzed for 110 coarctation interventions. Electronic medical records were reviewed, and primary endpoints were one of the following: (1) final analysis end date (June 2021), (2) patient death, or (3) most recent transcatheter or surgical reintervention. 64 (58.2%) interventions had a post-procedure CA gradient < 10 mmHg. Comparison of clinical patient outcome for acute success demonstrated no significant relationship using IMPACT (p = 0.70) criteria. There was no statistically significant difference between clinical success and failure for: pre- and post-treatment systolic gradients; absolute or percent change in systolic gradient; and pre-treatment aorta diameter. Clinical outcome and patient age did show a significant difference (p = 0.0093) with better clinical outcomes in older patients. Our analysis did not reveal a statistically significant difference between IMPACT criteria for successful treatment of CA and clinical outcome. These findings underscore a need to identify other clinical metrics that better predict outcome following CA balloon angioplasty treatment.

Descending thoracic aortic dissection after covered stent for adult aortic coarctation: Technical or physiopathologic?

Covered stent graft implantation is currently the most commonly used modality for the management of adult aortic coarctation. Although the risk of descending thoracic aortic dissection after covered stent graft implantation is low, sometimes it may cause serious medical consequences or even death. We report one adult aortic coarctation patient with early postoperative descending thoracic aortic dissection after covered stent graft implantation. The patient underwent second operation of thoracic endovascular aortic reconstruction and was discharged 6 days after the operation. This case is not rare, but we hope that the complete diagnosis and treatment process of this case and discussion pertaining to surgical treatment method and its complications could serve as a reference for clinicians in dealing with such situations.

A soldier's return to duty after minimally invasive correction of complex congenital cardiovascular disease

We report a case of incidental detection of severe aortic coarctation, severe secundum atrial septal defect, and bicuspid aortic valve in an active-duty military service member. A single complex minimally invasive procedure successfully corrected his coarctation and atrial septal defect allowing this patient to continue military service.

The Use of Stress Cardiovascular Imaging in Pediatric Population

Although not frequent in the pediatric population, ischemia could occur in children due to several congenital and acquired disease. Stress imaging is key for the non-invasive evaluation of myocardial abnormalities and perfusion defect in this clinical setting. Moreover, beyond ischemia assessment, it can provide complementary diagnostic and prognostic information in valvular heart disease and cardiomyopathies. When performed using cardiovascular magnetic resonance, it could detect, in addition, myocardial fibrosis and infarction, increasing the diagnostic yield. Several imaging modalities are currently available for the evaluation of stress myocardial perfusion. Advances in technologies have also increased the feasibility, safety and availability of these modalities in the pediatric age group. However, despite the established role of stress imaging and its increasing use in daily clinical practice, there are currently no specific guidelines, and little data are available in the literature on this topic. The aim of this review is to summarize the most recent evidence on pediatric stress imaging and its clinical application with a focus on the advantages and limitations of each imaging modality currently available.

Impaired Elastic Properties of the Ascending Aorta in Fetuses With Coarctation of the Aorta

Background Abnormal aortic elastic properties are major notable vasculopathy involved in coarctation of the aorta (CoA). However, there are no reports on aortic wall elastic characteristics in fetuses with CoA. Methods and Results Fifty-six fetuses with CoA and 56 normal controls were included in this prospective case-control study. The dimensions of the cardiac chamber, the size of the aorta, left ventricular myocardial performance indexes, and aortic elastic properties, including the global circumferential strain, fractional area change and mean longitudinal strain, were measured serially in utero. The global circumferential strain, fractional area change, and mean longitudinal strain in fetuses with CoA were smaller than those in the normal group at both the first and last examinations (18.50% versus 37.73% for global circumferential strain, 38.90% versus 57.55% for fractional area change, 6.61% versus 11.81% for mean longitudinal strain at first scan, 16.62% versus 42.05% for global circumferential strain, 36.54% versus 59.7% for fractional area change, 6.2% versus 11.46% for mean longitudinal strain at last scan, all P<0.001). There were negative correlations between aortic elastic properties and left ventricular myocardial performance indexes in fetuses with CoA (P<0.01). Aortic elastic properties were correlated positively with aortic isthmus size in fetuses with CoA (P<0.01). Conclusions Aortic strain and the fractional area change were decreased in fetuses with CoA. Impairments of these aortic elastic properties were associated with diminished heart function and aortic isthmus size in utero. Further large-scale longitudinal studies are required to confirm the potential predictive value of cardiovascular morbidity (ie, hypertension) in fetuses with CoA.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Revascularization of Left Subclavian to Common Carotid Artery Prepares for Covered Stent Implantation in Patients With Complex Aortic Coarctation

Seven adult patients underwent a two-stage treatment of complex coarctation (CoA), including surgical revascularization of the left subclavian artery (LSA) to left common carotid artery (LCCA), followed by transcatheter covered stent implantation. The majority of patients (5 of 7, 71%) received 1 covered stent (covered Cheatham Platinum stent: 8 zig/45 mm [n = 2], 10 zig/60 mm [n = 1], 10 zig/65 mm [n = 1]; BeGraft: 24/48 mm [n = 2]). In 1 patient (14%), the implantation of 2 covered stents (BeGraft 20/48 mm) was necessary. During a median follow-up of 2.4 years (interquartile range, 0.1 to 4.9 years), complications occurred in 3 of 7 patients (43%), including an asymptomatic but severe stenosis of the LSA bypass (n = 1), a recoarctation with a mild endoleak (n = 1), and a severe endoleak (n = 1). Surgical revascularization of the LSA to the LCCA can successfully prepare for covered stent implantation in complex CoA in adult patients. This two-stage approach was feasible and safe with complications occurring in 3 of 7 patients (43%). All complications were managed by catheter reintervention only.

Surgery for aortic recoarctation in children less than 10 years old: A single-center experience in Siberia, Russia

BACKGROUND

Persistence or recurrence of stenosis is a complication of initial coarctation repair. This study aims to report short-term outcomes of surgical management of recurrent coarctation and initial repair analysis.

METHODS

We retrospectively reviewed our experience with 51 patients undergoing recoarctation surgical repair between 2008 and 2019 using antegrade cerebral perfusion (ACP) technique.

RESULTS

Surgical correction included prosthetic patch aortoplasty in 23 (45%), resection with wide end-to-end anastomosis in 15 (29%), and a tube interposition graft in 13 (25%) patients. The median age at initial correction and reintervention was 12 months and 9 years. The median interval from primary repair to reintervention was 60 months. Initial repair analysis revealed 33% of patients had initial correction in the neonatal period, 72.5% of patients were done via a left thoracotomy approach and 63% of patients had end-to-end anastomosis at initial surgery.

CONCLUSION

Our study demonstrates that surgical repair of recurrent coarctation of the aorta using ACP technique can be performed safely and with excellent results.

Reducing Morbidity and Mortality in Patients With Coarctation Requires Systematic Differentiation of Impacts of Mixed Valvular Disease on Coarctation Hemodynamics

Background Despite ongoing advances in surgical techniques for coarctation of the aorta (COA) repair, the long-term results are not always benign. Associated mixed valvular diseases (various combinations of aortic and mitral valvular pathologies) are responsible for considerable postoperative morbidity and mortality. We investigated the impact of COA and mixed valvular diseases on hemodynamics. Methods and Results We developed a patient-specific computational framework. Our results demonstrate that mixed valvular diseases interact with COA fluid dynamics and contribute to speed up the progression of the disease by amplifying the irregular flow patterns downstream of COA (local) and exacerbating the left ventricular function (global) (N=26). Velocity downstream of COA with aortic regurgitation alone was increased, and the situation got worse when COA and aortic regurgitation coexisted with mitral regurgitation (COA with normal valves: 5.27 m/s, COA with only aortic regurgitation: 8.8 m/s, COA with aortic and mitral regurgitation: 9.36 m/s; patient 2). Workload in these patients was increased because of the presence of aortic stenosis alone, aortic regurgitation alone, mitral regurgitation alone, and when they coexisted (COA with normal valves: 1.0617 J; COA with only aortic stenosis: 1.225 J; COA with only aortic regurgitation: 1.6512 J; COA with only mitral regurgitation: 1.3599 J; patient 1). Conclusions Not only the severity of COA, but also the presence and the severity of mixed valvular disease should be considered in the evaluation of risks in patients. The results suggest that more aggressive surgical approaches may be required, because regularly chosen current surgical techniques may not be optimal for such patients.

Überraschende Echobefunde als Erstdiagnose eines angeborenen Herzfehlers im Erwachsenenalter

Angeborene Herzfehler (AHF) werden teilweise erst im Erwachsenenalter diagnostiziert, entweder weil sie erst dann klinisch auffällig werden oder bei vorausgegangenen Untersuchungen übersehen wurden. Im Rahmen einer routinemäßigen transthorakalen Echokardiografie (TTE) können in der kardiologischen Praxis oder Klinik angeborene kardiale Anomalien leicht fehlgedeutet werden, da der Fokus in der Erwachsenenkardiologie überwiegend bei erworbenen Herzfehlern, einer Kardiomyopathie, Klappenerkrankungen oder einer systolischen oder diastolischen Dysfunktion liegt. Demgegenüber spielt eine thematische Auseinandersetzung mit AHF häufig eine nur untergeordnete Rolle, die Erwartungshaltung hinsichtlich angeborener kardialer Anomalien ist eher gering und die Sinne für mögliche AHF oft nicht geschärft. Dieser Artikel soll dazu beitragen, die Wahrscheinlichkeit des Erkennens eines AHF im Rahmen der TTE-Untersuchung zu erhöhen.

RNA sequencing analyses in infants patients with coarctation of the aorta

BACKGROUND

Coarctation of the aorta (CoA) is a serious innate heart disease. Although surgery results are generally good, some complications such as recoarctation and aortic aneurysm or persistent hypertension were serious threats to patient's health. To better understand the pathology of CoA and its underlying molecular mechanism is particularly important for early diagnosis and preventing the occurrence of its complications. However, the mechanisms of CoA remain unclear, especially for infants.

METHODS

RNA sequencing (RNA-seq) was used to identify the differentially expressed genes (DEGs) in vascular tissues of 12 patients with CoA and 10 normal participants form 3- to 34-month-old infants. The characteristic of DEGs were validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunochemical staining (IHC) in vessels of patients with CoA and normal infants.

RESULTS

A total of 2491 DEGs with the false discovery rate less than 0.05(> 1.5-fold, P < 0.05 change) were identified, including 443 upregulated genes and 2048 downregulated genes. The Gene Ontology enrichment analysis showed that 26 out of the 2491 DEGs identified were associated with cardiovascular diseases. These 26 genes were mainly associated with extracellular matrix (ECM) and smooth muscle cells (SMCs) differentiation. Three DEGs, that is, CNN1 (calponin), α-actinin1 and myosin heavy chain 11 MYH11, were validated using qRT-PCR and Western blot analysis. In addition, immunochemical staining showed that calponin and MYH11 were highly expressed on the surface and in the deep layers of the thickened intima respectively.

CONCLUSION

This study comprehensively characterized the CoA transcriptome. Migration of extracellular matrix (ECM) and smooth muscle cells (SMCs) to the subendothelial space may be the major characteristic of CoA in infants.

A Neonatal Mouse Model for Pressure Overload: Myocardial Response Corresponds to Severity

The heart regeneration after apical resection and myocardial infarction in neonatal mice has been studied for years. However, the response of neonatal mouse heart under pressure overload is seldom explored. This study aimed to induce pressure overload in neonatal mice through a transverse aortic constriction (TAC) with different-gauge needles so as to investigate the effect of pressure overload on cardiomyocyte proliferation and hypertrophy in these mice. Myocardial hypertrophy was evaluated by echocardiographic, pathological, and molecular analyses. Cardiomyocyte proliferation was detected by immune-staining of phospho-histone H3, Ki67, and 5-bromo-2-deoxyuridine. Mild pressure overload induced with a 30-gauge needle stimulated cardiomyocyte proliferation, adaptive hypertrophy, and angiogenesis. The heart function was not hampered even 21 days after the surgery. Moderate pressure overload induced with a 32-gauge needle led to pathological myocardial hypertrophy, fibrosis, and heart failure 7 days after the surgery. The gene and protein expression levels of markers of hypertrophy and fibrosis increased in 32-gauge TAC group compared with that in sham and 30-gauge TAC groups. The mice barely survived after severe pressure overload induced with a 34-gauge needle. The findings of this study might provide new insights into cardiomyocyte proliferation and hypertrophy in neonatal mice under pressure overload.