Tachy-bradycardia syndrome, also known as sick sinus syndrome, occurs when the heart's natural pacemaker, the sinus node, weakens. This condition prevents the node from generating regular or sufficient electrical impulses to maintain a heart rate that meets the body's physiological needs. Consequently, the heart may beat too fast at times and too slow at others, leading to symptoms like lightheadedness, dizziness, shortness of breath, fatigue, palpitations, fainting, or near-fainting spells. Risk factors for sick sinus syndrome include chronic high blood pressure, coronary artery disease, cardiomyopathy, hypothyroidism, and advanced age.

Pacemaker implantation is a treatment method designed to deliver electrical impulses, replacing the disrupted conduction system. This helps maintain a stable heart rate and improves circulatory function. Currently, pacemakers are categorized into four main groups based on their design and function. Wireless pacemakers represent modern technology, offering a compact device that requires no leads. In contrast, traditional pacemakers utilize electrode leads to transmit signals. Among wired devices, single-chamber pacemakers stimulate the right ventricle, while dual-chamber pacemakers coordinate rhythm between the right atrium and right ventricle. Triple-chamber pacemakers, featuring cardiac resynchronization therapy, include an additional electrode through the coronary sinus to support the left ventricle, optimizing contractile force for the entire heart.

The selection of a pacemaker depends on the patient's age and medical condition. Single-chamber pacemakers are typically used for less complex cases but have limitations in synchronization. For younger individuals or those with high physical activity demands, dual-chamber pacemakers are preferred due to their ability to mimic the natural physiological rhythm between the atria and ventricles. Patients with severe heart failure may benefit from triple-chamber pacemakers, which help correct asynchrony between the two ventricles, thereby improving pumping efficiency. Wireless pacemakers are suitable for patients with weakened immune systems, a high risk of infection, chronic kidney failure, those undergoing dialysis, or individuals with vascular abnormalities.

Tam Anh General Hospital implants the new-generation Micra AV2 wireless pacemaker, which is the size of a capsule pill. Photo: Trung Vu

Technically, wired pacemakers require a surgical incision in the chest to create a pocket for the device under the muscle or skin. This procedure carries potential risks such as hematoma, infection, or lead damage over time. Replacing or adding new leads if problems arise is surgically complex and can increase the number of leads in the veins, obstructing blood flow back to the heart.

New-generation wireless pacemakers are extremely small, resembling a capsule pill, and weigh about 2 g, making them 93% lighter than conventional wired pacemakers (28 g). The device is implanted directly into the heart chamber via a catheter, eliminating the need for electrode leads or a subcutaneous pocket, which significantly reduces related complications. This device also offers more automatic and precise atrio-ventricular synchronization, allowing for early detection of arrhythmias and timely electrical impulse delivery when the heart beats too slowly or stops.

At Tam Anh General Hospital, the wireless pacemaker implantation procedure is performed by leading specialists, taking approximately 30-45 minutes, compared to 90-120 minutes for wired pacemakers. It is less invasive, minimizes pain, and ensures a better aesthetic outcome. This new type of pacemaker also boasts a battery life of up to about 16.7 years, while older generation wireless devices and other wired pacemakers typically last around 8-12 years.

For patients experiencing prolonged fatigue and dizziness, a comprehensive cardiology examination is recommended. Doctors may prescribe a 24-hour Holter ECG (continuous 24-hour electrocardiogram monitor) to accurately identify the type of arrhythmia. Based on these findings, the doctor can select the most suitable pacemaker model with features tailored to your daily activity level.

Doctor Nguyen Van Duong, MD, Specialist II

Interventional Cardiology Center

Tam Anh General Hospital, TP HCM