Downloaded from http://heart.bmj.com/ on February 16, 2016 - Published by group.bmj.com
Heart Online First, published on February 16, 2016 as 10.1136/heartjnl-2015-308042 Education in Heart
CONGENITAL HEART DISEASE IN ADULT PATIENTS
Challenges and management issues in adults with cyanotic congenital heart disease Craig S Broberg Correspondence to Dr Craig S Broberg, Knight Cardiovascular Institute, Oregon Health & Sciences University, UHN 62, 3181 SW Sam Jackson Pk Rd, Portland, OR 97239, USA; brobergc@ ohsu.edu
To cite: Broberg CS. Heart Published Online First: [please include Day Month Year] doi:10.1136/heartjnl2015-308042
INTRODUCTION A 22-year-old woman with a large unrepaired ventricular septal defect presented with significant haemoptysis. She was 22 weeks pregnant at the time. Her resting oxygen saturation was 78%, and her haematocrit was 66%. How should this complicated patient be managed? Should one recommend acute endotracheal intubation, phlebotomy or termination of her pregnancy? How should providers navigate the complicated decision-making needed in her critical situation? Adults with cyanotic congenital heart disease represent a wide variety of defects and histories. Some are those for whom corrective surgery either was not or could not be offered who, in spite of this, beat the odds and survived. Despite anecdotes of being told they would not live to reach the age of 4, 12 or 21, some have survived to their 60th decade or beyond. Others are those who had various palliative surgeries but did not achieve complete separation of pulmonary and systemic blood flow. For most, exertional tolerance is below normal, but they otherwise carry on with life, careers and family. Many are relatively stable, with often fewer hospital encounters, for example, than some of their palliated counterparts. They participate in activities that defy many providers’ expectations, such as maintaining full-time employment, air travel,1 living at high altitude2 or neurosurgery. They have developed important physiological adaptations that allow them to carry on, although with an ongoing risk that their fragile balance could be unfavourably tipped at any time. These patients rely on life-sustaining haematological adaptations to their chronic cyanosis, and are at risk of adverse consequences if such adaptations are out of balance. Clinical events may reflect either inadequate tissue oxygen delivery or embolism of thrombus or air. Complications include pulmonary thrombosis, haemoptysis, iron deficiency and cerebral vascular events. Patient’s presenting circumstances are highly variable and each patient deserves individualised care decisions. While all such patients should have regular contact with specialty congenital heart expertise, any provider who encounters these special patients should be aware of their particular nuances in order to be able to direct care in a prudent manner. This review will discuss the expected physiological adaptations and considerations for patient management. It is important to realise that each patient’s situation is unique and a highly individualised approach is necessary. Many cyanotic adults have coexisting pulmonary vascular disease (Eisenmenger syndrome). Such patients can often be distinguished from those
Learning objectives ▸ Understand the expected physiological adaptations to cyanotic heart disease. ▸ Recognise long-term complications of cyanotic heart disease and their clinical manifestations. ▸ Be able to make individualised recommendations in the care of patients with chronic cyanosis. without by the absence of a harsh systolic murmur. Such a murmur usually indicates stenotic pulmonary flow, preventing overcirculation. While many of the issues discussed herein apply to both groups, there are some fundamental differences that apply differently to the Eisenmenger population including the risk of haemoptysis, pulmonary artery enlargement and thrombosis, the role of pulmonary vasodilators and contraindication to pregnancy. Patients with cyanosis without Eisenmenger physiology may benefit from exploration of ways to improve pulmonary blood flow, if possible.
GENERAL ASSESSMENT Without exception all patients with cyanosis should have yearly visits with an experienced congenital heart specialist to coordinate care with primary care providers or other consultants as needed. The physical examination should record a resting oxygen saturation on room air measured in the fingers, and toes if a patent ductus is present, to check for differential cyanosis. Earlobe oxygen saturation tends to be a few percentage points higher than the fingers, a reminder of distinctions between central cyanosis and peripheral cyanosis.3 The physical examination should also note nail bed clubbing, surgical scars and any systolic murmur. Annual assessment should include baseline complete blood count for haemoglobin/haematocrit, platelet count, routine blood chemistries and iron stores. Serum uric acid may be beneficial since patients are at risk for gout. Brain natriuretic peptide is prognostic4 and may be considered for baseline assessment. Coronary artery disease is rare as lipids are usually low and there is little value in regular lipid screening.5 All patients deserve a baseline ECG and chest radiograph. Imaging should be done on occasion to assess for biventricular function.
SECONDARY ERYTHROPOIESIS The expected physiological response to chronic hypoxaemia is secondary erythropoiesis. This is an
Broberg CS. Heart 2016;0:1–6. doi:10.1136/heartjnl-2015-308042
1
Copyright Article author (or their employer) 2016. Produced by BMJ Publishing Group Ltd (& BCS) under licence.
Downloaded from http://heart.bmj.com/ on February 16, 2016 - Published by group.bmj.com
Education in Heart appropriate and necessary rise in both haemoglobin and red cell mass. Erythropoiesis differs significantly from polycythaemia since not all cell lines are increased. Leucocytes and platelets, either of which may contribute substantially to hyperviscosity in other conditions, are not overly expressed. Indeed, there is typically a lower than expected platelet count. Ideally, the patient’s own physiology will determine the level of haemoglobin. Oxygen saturation is an imperfect metric of right to left shunt since it reflects other issues such as ventilation/perfusion mismatch and tissue oxygen extraction in response to metabolic need. Over a 24 h period there will be an expected rise and fall in oxygen saturation, usually reflecting the patient’s regular activity. O2 saturation change is very often a mirror image of the heart rate response to similar activity (figure 1), with expected fluctuation. Hence, recorded levels should always be obtained at rest. Oftentimes, simply asking the patient what his or her resting oxygen saturation tends to be may help a provider gauge whether the severity of cyanosis for a presenting situation represents an acute deterioration. The degree of nail bed clubbing may also serve as a general indicator. Erythropoiesis to allow achievement of an optimal haemoglobin level ought to be set by the patient’s own need over time.6 Therefore, the degree of cyanosis should be reflected in the patient’s haemoglobin level, not saturation, akin to the haemoglobin A1c level indicating overall trends in blood glucose levels. The greater the degree of right to left shunt, the higher the haemoglobin ought to be in order to maintain a normal systemic oxygen transport (the product of oxygen content and cardiac output). There is an expected relationship between O2 saturation and haemoglobin,6 although there can be many factors that disrupt this expected
relationship. The regulatory mechanisms of erythropoiesis are more sophisticated than our current understanding or ability to regulate them. While there are recognised adverse consequences to excessive erythropoiesis, a general principle for providers is that the patient’s optimal haemoglobin should be set by the intrinsic demands of tissue hypoxia rather than titrated through any therapy we offer, including phlebotomy. Patients should be given the proper building blocks necessary for erythropoiesis and then left alone as much as possible.
IRON DEFICIENCY Iron deficiency is frequently encountered in cyanotic individuals.w7 Aetiology includes frequent phlebotomy, or bleeding such as from haemoptysis, epistaxis or menorrhagia. In addition to contributing to symptoms independent of anaemia, iron deficiency leads to production of a higher number of smaller cells with less haemoglobin per cell, translating to an overall lower haemoglobin without change in haematocrit. Since haemoglobin is the main determinant of oxygen delivery and haematocrit is the main determinant of blood viscosity, iron deficiency compromises systemic oxygen transport without lowering viscosity.w7 Cyanosis tends to induce a relative macrocytosis, therefore mean corpuscular volume (MCV) is not a reliable screening test for iron deficiency and should not be relied upon to exclude this.w8 Instead, transferrin saturation should be measured regularly to check for iron deficiency. Patients with transferrin saturation
Heart Online First, published on February 16, 2016 as 10.1136/heartjnl-2015-308042 Education in Heart
CONGENITAL HEART DISEASE IN ADULT PATIENTS
Challenges and management issues in adults with cyanotic congenital heart disease Craig S Broberg Correspondence to Dr Craig S Broberg, Knight Cardiovascular Institute, Oregon Health & Sciences University, UHN 62, 3181 SW Sam Jackson Pk Rd, Portland, OR 97239, USA; brobergc@ ohsu.edu
To cite: Broberg CS. Heart Published Online First: [please include Day Month Year] doi:10.1136/heartjnl2015-308042
INTRODUCTION A 22-year-old woman with a large unrepaired ventricular septal defect presented with significant haemoptysis. She was 22 weeks pregnant at the time. Her resting oxygen saturation was 78%, and her haematocrit was 66%. How should this complicated patient be managed? Should one recommend acute endotracheal intubation, phlebotomy or termination of her pregnancy? How should providers navigate the complicated decision-making needed in her critical situation? Adults with cyanotic congenital heart disease represent a wide variety of defects and histories. Some are those for whom corrective surgery either was not or could not be offered who, in spite of this, beat the odds and survived. Despite anecdotes of being told they would not live to reach the age of 4, 12 or 21, some have survived to their 60th decade or beyond. Others are those who had various palliative surgeries but did not achieve complete separation of pulmonary and systemic blood flow. For most, exertional tolerance is below normal, but they otherwise carry on with life, careers and family. Many are relatively stable, with often fewer hospital encounters, for example, than some of their palliated counterparts. They participate in activities that defy many providers’ expectations, such as maintaining full-time employment, air travel,1 living at high altitude2 or neurosurgery. They have developed important physiological adaptations that allow them to carry on, although with an ongoing risk that their fragile balance could be unfavourably tipped at any time. These patients rely on life-sustaining haematological adaptations to their chronic cyanosis, and are at risk of adverse consequences if such adaptations are out of balance. Clinical events may reflect either inadequate tissue oxygen delivery or embolism of thrombus or air. Complications include pulmonary thrombosis, haemoptysis, iron deficiency and cerebral vascular events. Patient’s presenting circumstances are highly variable and each patient deserves individualised care decisions. While all such patients should have regular contact with specialty congenital heart expertise, any provider who encounters these special patients should be aware of their particular nuances in order to be able to direct care in a prudent manner. This review will discuss the expected physiological adaptations and considerations for patient management. It is important to realise that each patient’s situation is unique and a highly individualised approach is necessary. Many cyanotic adults have coexisting pulmonary vascular disease (Eisenmenger syndrome). Such patients can often be distinguished from those
Learning objectives ▸ Understand the expected physiological adaptations to cyanotic heart disease. ▸ Recognise long-term complications of cyanotic heart disease and their clinical manifestations. ▸ Be able to make individualised recommendations in the care of patients with chronic cyanosis. without by the absence of a harsh systolic murmur. Such a murmur usually indicates stenotic pulmonary flow, preventing overcirculation. While many of the issues discussed herein apply to both groups, there are some fundamental differences that apply differently to the Eisenmenger population including the risk of haemoptysis, pulmonary artery enlargement and thrombosis, the role of pulmonary vasodilators and contraindication to pregnancy. Patients with cyanosis without Eisenmenger physiology may benefit from exploration of ways to improve pulmonary blood flow, if possible.
GENERAL ASSESSMENT Without exception all patients with cyanosis should have yearly visits with an experienced congenital heart specialist to coordinate care with primary care providers or other consultants as needed. The physical examination should record a resting oxygen saturation on room air measured in the fingers, and toes if a patent ductus is present, to check for differential cyanosis. Earlobe oxygen saturation tends to be a few percentage points higher than the fingers, a reminder of distinctions between central cyanosis and peripheral cyanosis.3 The physical examination should also note nail bed clubbing, surgical scars and any systolic murmur. Annual assessment should include baseline complete blood count for haemoglobin/haematocrit, platelet count, routine blood chemistries and iron stores. Serum uric acid may be beneficial since patients are at risk for gout. Brain natriuretic peptide is prognostic4 and may be considered for baseline assessment. Coronary artery disease is rare as lipids are usually low and there is little value in regular lipid screening.5 All patients deserve a baseline ECG and chest radiograph. Imaging should be done on occasion to assess for biventricular function.
SECONDARY ERYTHROPOIESIS The expected physiological response to chronic hypoxaemia is secondary erythropoiesis. This is an
Broberg CS. Heart 2016;0:1–6. doi:10.1136/heartjnl-2015-308042
1
Copyright Article author (or their employer) 2016. Produced by BMJ Publishing Group Ltd (& BCS) under licence.
Downloaded from http://heart.bmj.com/ on February 16, 2016 - Published by group.bmj.com
Education in Heart appropriate and necessary rise in both haemoglobin and red cell mass. Erythropoiesis differs significantly from polycythaemia since not all cell lines are increased. Leucocytes and platelets, either of which may contribute substantially to hyperviscosity in other conditions, are not overly expressed. Indeed, there is typically a lower than expected platelet count. Ideally, the patient’s own physiology will determine the level of haemoglobin. Oxygen saturation is an imperfect metric of right to left shunt since it reflects other issues such as ventilation/perfusion mismatch and tissue oxygen extraction in response to metabolic need. Over a 24 h period there will be an expected rise and fall in oxygen saturation, usually reflecting the patient’s regular activity. O2 saturation change is very often a mirror image of the heart rate response to similar activity (figure 1), with expected fluctuation. Hence, recorded levels should always be obtained at rest. Oftentimes, simply asking the patient what his or her resting oxygen saturation tends to be may help a provider gauge whether the severity of cyanosis for a presenting situation represents an acute deterioration. The degree of nail bed clubbing may also serve as a general indicator. Erythropoiesis to allow achievement of an optimal haemoglobin level ought to be set by the patient’s own need over time.6 Therefore, the degree of cyanosis should be reflected in the patient’s haemoglobin level, not saturation, akin to the haemoglobin A1c level indicating overall trends in blood glucose levels. The greater the degree of right to left shunt, the higher the haemoglobin ought to be in order to maintain a normal systemic oxygen transport (the product of oxygen content and cardiac output). There is an expected relationship between O2 saturation and haemoglobin,6 although there can be many factors that disrupt this expected
relationship. The regulatory mechanisms of erythropoiesis are more sophisticated than our current understanding or ability to regulate them. While there are recognised adverse consequences to excessive erythropoiesis, a general principle for providers is that the patient’s optimal haemoglobin should be set by the intrinsic demands of tissue hypoxia rather than titrated through any therapy we offer, including phlebotomy. Patients should be given the proper building blocks necessary for erythropoiesis and then left alone as much as possible.
IRON DEFICIENCY Iron deficiency is frequently encountered in cyanotic individuals.w7 Aetiology includes frequent phlebotomy, or bleeding such as from haemoptysis, epistaxis or menorrhagia. In addition to contributing to symptoms independent of anaemia, iron deficiency leads to production of a higher number of smaller cells with less haemoglobin per cell, translating to an overall lower haemoglobin without change in haematocrit. Since haemoglobin is the main determinant of oxygen delivery and haematocrit is the main determinant of blood viscosity, iron deficiency compromises systemic oxygen transport without lowering viscosity.w7 Cyanosis tends to induce a relative macrocytosis, therefore mean corpuscular volume (MCV) is not a reliable screening test for iron deficiency and should not be relied upon to exclude this.w8 Instead, transferrin saturation should be measured regularly to check for iron deficiency. Patients with transferrin saturation
