Perioperative management of a patient with morbid obesity and severe cardiomyopathy: a case report and literature review

Abstract

As the obesity epidemic continues to escalate, the need for bariatric surgery will increase. Patients with severe cardiomyopathy and heart failure have historically been considered at high risk for perioperative complications and thus excluded from bariatric surgery. We herein describe a patient with morbid obesity, severe cardiomyopathy, and heart failure who successfully and safely underwent bariatric surgery and achieved significant weight loss and overall cardiac function improvement 1 year later. Although data are sparse, there is certainly evidence to suggest that significant weight reduction may confer a mechanism of ventricular reverse remodeling and subsequent clinical improvement.

Introduction

Obesity cardiomyopathy (OCM) is a metabolic myocardial disease in individuals with obesity that cannot be explained by only diabetes, hypertension, coronary artery disease, or other etiologies.^1–3 OCM results in impaired left ventricular function and presents as systolic or diastolic heart failure, with a broad clinical spectrum ranging from asymptomatic subclinical cardiac dysfunction to New York Heart Association (NYHA) functional class IV dilated cardiomyopathy. ² Clinical symptoms include dyspnea, wheezing, exercise intolerance, and lower extremity edema. ⁴ These symptoms have been attributed to the mechanical consequences of structural remodeling of the heart.^4–6 Individuals with obesity develop multiple cardiac structural changes, including left atrial enlargement, left ventricular centrifugal hypertrophy, and left ventricular dilatation. The most important mechanisms in the development of OCM are metabolic disturbances (insulin resistance, increased free fatty acid levels, and increased adipokine levels), activation of the renin–angiotensin–aldosterone and sympathetic nervous systems, myocardial remodeling, small vessel disease (both microangiopathy and endothelial dysfunction), and other comorbidities linked to obesity (e.g., diabetes and hypertension).^1–3,7,8

In this case, we provide various perioperative management strategies to avoid perioperative adverse cardiovascular events in patients with OCM. In addition, this case suggests that bariatric surgery may confer a mechanism of ventricular reverse remodeling and subsequent clinical improvement.

Case presentation

A 30-year-old man was admitted to our hospital on 8 July 8 2021 because of morbid obesity (height: 175 cm, weight: 143 kg, body mass index: 46.7 kg/m²). The patient had a long history of hypertension and diabetes. He had been admitted and treated at Luzhou People’s Hospital 1 month previously for edema of both lower limbs and difficulty lying flat. He was diagnosed with cardiomyopathy and congestive heart failure with a left ventricular ejection fraction of 13%. The patient attempted to lose weight through diet and exercise but was unsuccessful. Therefore, he visited our hospital for bariatric surgery. Cardiac magnetic resonance imaging revealed enlargement of the whole heart, thickening of the left ventricular wall and septum (approximately 2 cm at the thickest part; i.e., posterior wall and septum), and a weakened heartbeat (Figure 1). In addition, the left ventricular measurements showed that the ejection fraction was 23.81%, the end-diastolic volume was 348.84 mL, the end-systolic volume was 265.78 mL, the stroke volume was 83.06 mL, the cardiac output was 7.94 L/min, and the left ventricular mass was 427.55 g. The patient was diagnosed with metabolic syndrome, OCM, heart failure, hypertension, diabetes, nephritic syndrome, and obstructive sleep apnea syndrome. He provided written consent for both treatment and publication of this case report. The reporting of this study conforms to the CARE guidelines. ⁹

Figure 1.

Cardiac magnetic resonance imaging findings. The whole heart was enlarged, and the left ventricular wall and septum were thickened.

After a multidisciplinary team discussion, we suggested that the patient attempt to lose weight through diet and further improve his cardiac function before surgery. The cardiologists developed a series of guideline-directed medical treatments to reduce the cardiac preload and afterload. In addition, considering the presence of nephritis syndrome, the nephrologists suggested treatment with an angiotensin receptor blocker to reduce urinary protein and protect the patient’s renal function. Moreover, the nutritionists recommended a short-term low-calorie diet to properly control the patient’s weight before surgery, and this diet was then replaced with a special medical formula food for kidney disease (<1 week). The endocrinologists adjusted the patient’s insulin regimen to improve his blood glucose fluctuations. After 2 weeks of treatment, the patient’s blood glucose, blood pressure, and heart rate were effectively controlled; his physical condition had significantly improved; and his cardiac function had recovered to NYHA functional class II to III. Additionally, he had lost 10 kg in weight because of the diet change. Therefore, we scheduled laparoscopic sleeve gastrectomy under general anesthesia for further treatment.

At 11:50 on 23 July 2021, after the patient entered the operating room, we began monitoring his noninvasive blood pressure, electrocardiogram, and pulse oxygen saturation. Before general anesthesia, radial artery catheterization and deep vein catheterization were performed under local anesthesia for continuous invasive blood pressure and cardiac output monitoring. A combination of glucose, insulin, and potassium (500 mL of 10% glucose + 10 mL of 10% potassium chloride + 10 U of insulin) was administered via pump to improve the myocardial metabolism and prevent arrhythmia. At 12:00, after sufficient preoxygenation, anesthesia was induced and an endotracheal tube was placed. The patient’s blood pressure dropped after anesthetic induction at 12:05, and phenylephrine was administered via pump at 0.1 to 1.0 µg/kg/min to maintain the blood pressure. Transesophageal echocardiography was used to monitor the patient’s cardiac status, followed by slow input of 500 mL of fluid and a gradual reduction of phenylephrine. The operation was completed at 14:30, and 10 mL of ropivacaine was given for incision infiltration anesthesia. The intraoperative bleeding volume was 20 mL, and the fluid infusion volume was 700 mL. After the operation, the patient was transferred to the intensive care unit for further treatment and monitoring. One day later, he was successfully extubated and transferred back to the general ward. On 30 July 2021, the patient had fully recovered and was discharged from the hospital.

At the 1-year follow-up, the patient had lost 52 kg of weight. Unexpectedly, his cardiac function had also significantly improved. His daily activities no longer caused fatigue, palpitations, or dyspnea, and he was able to exercise, which had been unimaginable before surgery. In addition, during follow-up, the patient had stopped taking irbesartan, furosemide, and prazosin, and the irbesartan had been replaced with valsartan. The patient had NYHA functional class IV symptoms on admission, and he still had NYHA functional class II to III symptoms despite effective treatment before bariatric surgery; at the 1-year follow-up, however, his cardiac function had recovered to NYHA functional class I (Table 1).

Table 1.

Comparison of weight and echocardiographic parameters before and after bariatric surgery.

	Two months before surgery	Two weeks before surgery	Day of surgery	One week after surgery	One-year follow-up
Weight (kg)	145	143	133	130	81
BMI (kg/m2)	47.3	46.7	43.4	42.4	26.4
HR (beats/minute)	121	105	97	99	87
BP (mmHg)	191/140	178/117	159/94	151/89	136/74
LA diameter (mm)	–	43	43	42	39
LV diameter (mm)	–	71	65	66	60
RA diameter (mm)	–	45 × 55	44 × 55	40 × 53	38 × 43
RV diameter (mm)	–	27	28	27	25
IVST (mm)	–	14	14	13	11
LVPW (mm)	–	13	13	12	11
LVEF (%)	13	25	31	37	54
LVFS (%)	–	15	18	18	26
NYHA classification	IV	III–IV	II–III	II–III	I

BMI, body mass index; HR, heart rate; BP, blood pressure; LA, left atrial; LV, left ventricular; RA, right atrial; RV, right ventricular; IVST, interventricular septal thickness; LVPW, left ventricular posterior wall thickness; LVEF, left ventricular ejection fraction; LVSF, left ventricular fractional shortening; NYHA, New York Heart Association.

Discussion

Although the patient in our case was only 30 years old, his daily life was very difficult and he was unable to work because of morbid obesity and NYHA functional class IV symptoms. Because lifestyle adjustments such as exercise and diet had not been effective in losing weight, bariatric surgery became an urgent option for him. ¹⁰ The patient’s poor physical condition presented a great challenge for the anesthesiologist and surgeon throughout the perioperative period. Therefore, a multidisciplinary team discussion was of vital importance to improve the patient’s NYHA functional class IV symptoms. Fortunately, after 2 weeks of treatment and diet, the patient lost 10 kg of body weight, his physical condition significantly improved, and his cardiac function recovered to NYHA functional class II to III symptoms.

The intraoperative anesthetic management is this case was also extremely precarious. Before the initiation of anesthesia, a combination of glucose, insulin, and potassium was administered in an attempt to provide myocardial protection and prevent arrhythmia. This combination is widely used in patients with myocardial injury, severe infection, and trauma. ¹¹ Insulin can promote glucose transport into cardiomyocytes to increase the energy supply and improve the metabolism of the ischemic myocardium. Because of the special respiratory physiology of patients with obesity, the oxygen saturation is prone to rapidly decrease during anesthetic induction. ¹² Therefore, positive end-expiratory pressure (PEEP) was administered through the patient’s mask during the preoxygenation stage, and mechanical ventilation was administered in a timely manner after induction to prevent atelectasis and hypoxia. Studies have proven that during muscle relaxation under general anesthesia, the use of 10 cmH₂O PEEP in patients with morbid obesity can improve ventilation mechanics, increase the oxygen saturation, and reduce the alveolar–arterial oxygen partial pressure difference. ¹³ However, vasoconstriction drugs and fluids are required to prevent PEEP-induced hypotension. In this case, we clarified the cause of the patient’s hypotension through transthoracic echocardiography and infused a specific volume of fluid under the guidance of transesophageal echocardiography; this not only avoided continuous hypotension but also avoided aggravation of the patient’s heart failure by excessive infusion. Moreover, postoperative multimodal analgesia for obese patients can improve lung function and prevent pneumonia. We adopted a combination of incision infiltration anesthesia and patient-controlled analgesia to avoid large doses of opioids. Such patients must be transferred to the intensive care unit for continuous professional care and adjuvant therapy. In addition, early continuous positive airway pressure-assisted ventilation is recommended because of the high risk of upper airway obstruction after extubation. ¹²

Patients with severe cardiomyopathy were historically considered at high risk for perioperative complications such as myocardial infarction, and they were therefore excluded from bariatric surgery. Patients with NYHA functional class III to IV symptoms and severely reduced systolic function have a higher risk of death during the perioperative period. ¹⁴ The present case demonstrates that heart failure in some patients with obesity may respond well to bariatric surgery, which may be a feasible intervention in centers where anesthetic and intensive care expertise supports the perioperative management of these critically unwell patients. ¹⁵ As the obesity epidemic continues to escalate, the need for bariatric surgery will increase in this population of patients with severe cardiomyopathy and heart failure. ⁴ This case emphasizes that bariatric surgery is extremely helpful for achieving significant weight reduction and improving overall cardiac function for patients with obesity and heart failure. Bariatric surgery has been shown to improve insulin resistance and lead to the resolution of diabetes mellitus, improve hyperlipidemia and hypertension, and possibly eliminate obstructive sleep apnea syndrome.^2,6,16 In patients with obesity and altered ventricular function, surgical weight loss may result in ventricular reverse remodeling.^16–18 There are data to suggest that significant weight reduction reduces the left ventricular cavity size and improves cardiac hemodynamics, diastolic filling, NYHA functional class, and overall cardiac function.^2,6,18

Conclusion

We have herein described a patient with morbid obesity, severe cardiomyopathy, and heart failure who successfully and safely underwent bariatric surgery and achieved significant weight loss and overall cardiac function improvement 1 year later. This case provides some perioperative management strategies for such critical patients, helping to avoid perioperative adverse cardiovascular events. Additionally, although data are sparse, there is certainly evidence to suggest that bariatric surgery may confer a mechanism of ventricular reverse remodeling and subsequent clinical improvement.

Data availability statement

All data generated or analyzed during this study are included in this published article and its additional information file.

Ethics statement

The patient provided written consent for both treatment and publication of this case report. Because this is a case report, ethics approval was not required. The patient’s details were de-identified.